1. Life. In theory life in the universe appeared when electric currents went through the masses of hydrogen, ammonia, water and methane, therefore creating something animate out of a set of inanimate chemicals. In practice, for a few decades the scientists have been trying to achieve a similar effect on a smaller scale, but so far no one has been able to produce the Holy Grail — turning something lifeless into something that is actually live, such as a single-cell organism. The life itself, it seems, is a scientific anomaly that should not happen in this Universe according to the existing laws of chemistry.
2. Death. You've heard it before: two things you cannot avoid in life are death and taxes. Well, this is a very human-centric view of things, as it turns out there's a variety of species (most of them vertebrates) that only get better with age. Some turtles, it seems, only get healthier and produce more children with age. Moreover, scientists are aware only of non-natural causes of their deaths — being run over by a truck or attacked by a bird. Are those turtles immortal, or are we observing just a small stage of their lifecycles (which could eclipse ours by generations)?
3. Dark matter. It's not embarrassing for scientists to admit they don't know something. After all, there are plenty of little details that remain unknown in many branches of science. So not knowing what constitutes dark matter would be an acceptable excuse, if it weren't for the fact that dark matter comprises 96% of the Universe. We know that the Universe keeps expanding, but we cannot quite describe how and what happens to the space that used to be compacted previously. Dark matter is the giant elephant in the room in discussions related to astronomy or physics — we don't know what it is, we've never seen it, and only infer its existence, yet roughly speaking it's a major ingredient in the Universe we live in.
4. Varying constants. Physical constants are warm and fuzzy. We don't know why they have the value they have, but we always substitute them into our equations and formulas, relying on decades of scientific research behind us, and the fact that they are, well, constants. However, there's a fairly determined group of scientists that is looking into certain scientific constants and finding that their values have changed as the Universe aged. Determined might be an understatement, as anyone willing to travel to Gabon and mess with uranium there is certainly dedicated. What they're finding is that the constants describing nuclear reactions were different two billion years ago compared to current constants.
5. Newton's inverse square law. In 1994 scientists at Los Alamos National Laboratory figured out they had a bug with Pioneer probes. Contrary to the Newton's inverse square law, the Pioneers were drifting off course. They hired Slava Turyshev out of Jet Propulsion Lab to investigate the small bug, which was most likely to blame on some contamination or error in Pioneer design. 14 years later the bug still stands unresolved. Together with NASA the scientists have gone through heaps of papers figuring out what could go wrong, and the answer is still up in the air. If unresolved, the Pioneer trajectory might become the first evidence that it's time to rethink Newton's inverse square law.
6. Homeopathy. When it works, you hear all about it. Homeopathy is almost like religion, in the sense that it attracts either staunch believers, or extreme sceptics. The idea of diluting a certain ingredient with copious amounts of water doesn't sit well with the majority of chemists, who point out that such small proportions call for a chance of the entire solution being water. Nevertheless, in Brooks' book there's an attempt at the explanation of what might be causing homeopathic effect — changes in molecular structure of water depending on the chemicals that it's been in contact with, even if the chemicals have been filtered out. However, it's still an attempt at best, since the scientific experiments that do achieve positive results are generally not reproducible.
7. Placebo effect. Perhaps related to the previous thing we don't understand, placebo effect has some interesting features. The patient knowing or suspecting that they might be receiving a placebo behaves differently than those without any knowledge. Are we comforted by the sight of people in white robes and our local pharmacist dealing out the regular dose of medication? Or does body start producing entirely different set of hormones with mind suspecting that the recovery process is near. Placebo, if figured out, might become a huge money saver with the current drug prices, and hence attracts scientific research. The only thing missing? A definitive conclusion on the placebo effect.
8. Free will. A certain amount of human ideology rests on the idea of free will. So the idea of the body just reacting to some responses outside of the brain is uncomfortable. But picture this. You're in bed, it's time to get up, yet you want to spend a few more minutes in bed. Your conscious mind is sending the signals for the body to get vertical, and yet at some point, probably between the thoughts of pending shower and commute to work, you get up. The final decision done by something unconscious, something you don't really have control over. While your conscious mind can submit an application to this unknown organ and request something happening, the body movements and behavior are triggered by something that is still largely unknown for science.
9. Cold fusion. It became one of the most ridiculous scientific ideas to get associated with, and no scientist would touch it nowadays with a 40-foot pole, since it brings the stigma. However, as some point out, peer pressure is pathway to missing out on some potential innovations in the field. What's currently reproducible is the effect of cold fusion on a plastic called CR39. Placed by a piece of depleted uranium, CR39 shows similar patterns of radiation as placed into a cold fusion experiment.
10. Life on Mars. The Viking probes were declared to contain no evidence of life on Mars. The only person in the room who disagreed with the announcement was a bacteriological researcher, who came up with a clever idea of detecting life (fart reference coming soon). By adding radioactive isotopes to the nutrients fed into the foreign soil, the researchers would get any evidence of carbon-based life to produce gas (there it is), and by the virtue of having the food injected with isotopes, the Geiger counter would go ballistic, and hence you could validate existence of life in the soil, even if other tests came negative.
11. WOW signal. One would argue that scientists at SETI (Search for Extra-Terrestrial Intelligence) have a pretty monotonous job. They're waiting for a signal on 1420 MHz frequency. Why 1420? That's the frequency of hydrogen, the most prevalent element in the Universe, so hopefully those extra-terrestrials will arrive at the same idea when sending the signal. So far no signal has arrived. Except on August 15th, 1977, when the signal came. It was very distinct, and caused Jerry Ehman to write "Wow!" on the margin of the printout. The signal never repeated, and the SETI folks have not heard anything similar since then.
12. Mimivirus is an interesting virus that does not seem to affect humans, except for the unique cases, when it actually does. It's the virus that fight cancer cells among others, and hence draws a great deal of research attention.
13. Sex. If you've read this far, here's a bonus entry. Yes, sex is one of those things that scientists do not quite understand (insert a proper nerd joke here). Looking at overall picture, the animal kingdom provides a great variety of alternative means of reproduction, that are much more efficient as far as number of offspring and the quality of gene preservation. A number of reptiles and fish are all-female or all-unisex species, copying themselves for the purposes of reproduction. Moreover, a number of species, like water fleas, can reproduce either sexually or asexually. You'd think that the species produced through asexual reproduction would be somehow inferior to the ones that appeared as a result of a sexual act, but there's no solid scientific data to prove that or the opposite. What remains enigmatic is that if asexual reproduction would provide you with 2x the population compared to sexual (and that leaves out the time and energy spent on finding a mate, taking her to dinners and consequent ring shopping), why didn't the entire animal world switch to asexual, as it's obviously a more efficient process.

1. Their research department meets with target groups, compiles presentations for the upper management, which then occasionally hands those reports over to the development department.
2. Their research or marketing department comes up with competitive matrix of the products available from competition. In a meeting then, executives see that their product is missing a feature, and hence the development department is assigned the task of adding "an Internet-enabled installer" to the product, since everybody else offers them, thereby creating market expectations.

Subject to Change is a book, written by four Adaptive Path veterans describing new approaches to product development and innovation. Who are they to have the authority over the subject? Adaptive Path is a consulting shop helping large and small companies with product design, Web design and industrial design. They're perhaps mostly known to the general public for coining the term AJAX, and articulating the idea of building dynamic Web sites with asynchronous data retrieval, but they certainly didn't invent the technology. Their design experience is behind many products we use today, but due to licensing agreements they're not always at liberty to disclose their customers.

So what do Adaptive Path designers advocate?

1. Making the design emotional. While the idea itself is not new, this is something that product manufacturers have to face sooner or later. Early Kodak cameras did not succeed because of superior technical qualities or ease of film development — they managed to cross this emotional barrier, where people who previously thought "This is too complicated" after getting a glimpse of the ad or product demo thought "Even I might be able to enjoy this."
2. Understand people's needs outside of your company-approved usability testing guides. Two great examples provided by the book are Adaptive Path's own usability study of Epinions.com — product review and comparison shopping site. When a woman showed up for usability test with her newborn baby, she was frequently distracted by baby's needs during the test. Bad test candidate? Vice versa. Adaptive Path learned how confusing it could be for someone who needs to get away from the comparison shopping process to come back and quickly realize where they were in the process. Another example has to deal with babies as well — after watching new mothers use the diaper wipes at their homes, Kimberly-Clark researchers redesigned their diaper wipe container to be easily accessible with just one hand.
3. Make the whole system coherent, not just patch new interfaces throughout product holes. Financial companies and banks certainly suffer from a desire by single group to innovate the others out. My own example — I go to Fidelity Web site, and upon login offered to also check my NetBenefits(SM) or check out the FullView(R). Now, there might be customers who think in those terms, but I surely did not log in to check NetBenefits(SM) or do FullView(R) or check out mySmart Cash Account (SM), I just wanted to find out how my investments were doing. A simple graph would do. Yet my options from Fidelity are either downloading quarterly PDF account statements, and then punching the numbers to create a graph, or going to Account Positions page, where I can view the graphs for every single stock and bond I own for any time value except the time span that I need — from the day I bought the security to today. This is not a rant on Fidelity Investments in general, this is just another example of different groups within the company handling such things as stocks, bonds, retirement planning, cash investments, quarterly account reports, and Web site design. Each group probably doesn't think highly of the existing user interface, and hence the desire to introduce that new simple interface, call it a different name, and expect the customers to get on with a program and use it.

Authors provide a lot of good case studies for design successes and failures to support their point. Case studies are borrowed from outside literature or told in first person — Adaptive Path's customer names are changed to be KeyboardCo or FinanceCo to protect the innocent. The book explores several different permutations of design and relevance:

1. When design is great, and product is relevant, market success is a given. The example is Apple iPod series. Somewhat less known example is Google Calendar, that outgrew Yahoo! Calendar and MSN Calendar, even though all 3 calendars are tied into Web-based e-mails, and Yahoo! and Hotmail both have market shares multiple of Gmail's.
2. When design is great, but product is not relevant, market success will be extremely hard to achieve. Segway scooter and Apple G4 Cube come to mind.
3. When design is bad, but product is relevant, market success will quickly turn into failure as competitors copy the product and invest in design. Diamond Rio, the pioneer of digital music player industry, learned a hard lesson that way.
4. When design is bad, and the product is irrelevant, it's possible it will never even come out in the market. Adaptive Path's own example of KeyboardCo wanting to implement a downloadable music service right on the keyboard is a good example of this.