Well, if all factors are equal it doesn't vary, otherwise every run on the same machine would vary and it would be useless. The point is that there enough differing variables between machines that it becomes useful for finger printing (and also for identifying specific hardware/driver/os/browser signatures). It would be used in conjunction with other techniques in practise I am sure.

Different drivers, OS's, web browsers, GPU's etc all have slight effects when asked to render something onto the canvas. The trick is that the raw resultant bits can then be captured trivially using getImageData() and then sent back to the tracker site (after hashing or what have you to reduce the size). It'll render the same way every time on your machine, but will differ to someone else's. (Showing my age here), kind of like how you could easily see the difference between the old Voodoo and TNT2 graphics card by how they rendered.

An insightful post, I'd love to hear if you had an ideas on how the system could be improved?

Please mod this up and GP down. +5 Ignorant.

This is a good point. If we ever get to the point of being able to efficiently convert matter into energy with negligible loses, then science fiction becomes far more believable. The "scarcity" of resources equation hard wired into our biology would be irrelevant. The physics is simple, but the engineering is a real bugger.

Don't be put off by the "C++" in the title. Most of the concepts are applicable to any language. It's about the engineering behind large scale software development.

If every university simply taught this book, software development would be called software engineering. Written in 1996, and still we have not learned the lessons. Flawed. Wordy. Partially out of date. And yet, if you understand and apply the concepts in this book, you will design applications and systems of the standard that everyone actually expects software to be at (rather than where it is).

To be fair, you basically set this kid up for failure. What you describe is a significant engineering challenge, and you gave it to a computer science graduate, with no experience. If you gave this to someone with 10 years under their belt, I'm sure they could create a lovely maintainable package; but as it is, you should start over. You may as well have asked him/her to design the Golden Gate Bridge. Computer science does not teach engineering, there is no way this kid could have had the necessary skills.

Mod parent up!

The whole point of this, the whole point, is to make specialized idiot-proof diagnostic tools. Did you watch the Ted talk? It's short and informative. If you see the vid, you'll see that many of these places have a fancy microscope already that no one can use. With this thing they can create a specialized single use malaria detector for example. Very little training is required to insert slide, look at image, malaria? Yes/No. That's the point of this, that's what they are trying to achieve. It's a good idea, and it could transform diagnosis in the third world.

It seems to me that you delight in being wrong. Australian aboriginals worked, on average, 6 hours per day. Australian history is quite recent, this statement is not in dispute. I'm not trying to suggest that this was the case for any other hunter-gatherer society (I'm quite ignorant outside of this area), but the idea that Australian aboriginals had a relatively easy life is neither minority view nor controversial.

On the "life span" topic, you seem to indicate that people are uniformly dropping off in their 30's, which was simply not the case. You were quite likely to die in childhood (particularly infancy), but if you got through that, quite likely to creek on past 50. Why present this as if people are dying in their 30's, ground down by poor diet and harsh conditions? Simple nonsense.

More ignorance. Life spans were not in the "low 30's" for indigenous or Europeans. Average life expectancy was predominantly impacted by infant mortality rates. Once out of childhood, you could reasonably expect to hit late 50's or 60 odd. Leisure time is again something you are simply wrong about. From all evidence, including first person accounts from early explorers; life was easy. In fact, there is a reasonable argument to be made that this is why such little advancement was made over 40000 years. If life is easy and food is plentiful, why do anything different? But continue on, I'm interested in what other sweeping statements you will make inspite of all evidence to the contrary.