You forgot:
8) Throw card away since it is useless now.

No idea how it is in the USA, but in Europe the magnet strip is hardly used anymore. Too insecure. Some people even destroy it on purpose. Instead a chip in the card used. Not a NFC chip. So, how do you destroy one chip in a microwave oven, but leave another chip on the same card intact?

Oh, an yes, there is one party, for which this problem definitely pays: The bank. Getting money for each transaction and getting money for chargebacks.

True. But how many don't check their accounts regularly? How many double charges remain unnoticed? Maybe it pays for the merchant?

Bad idea for whom?

As a former HS science teacher, I was part of a department that outlawed all plant experiments.

You can be proud of yourself. Stifle kids interest in science just because the are not trained and experienced scientist. Who made you a teacher?

Here I found an even more pessimistic view: http://www.astronomycafe.net/qadir/q2720.html

Safe speeds for current technology would be only slightly higher than space shuttle speeds especially if interstellar space contains chunks of comet ice.

If this is true... forget your 100s years. Make it 10000s.

100s years? At what speed? According to this article:http://arxiv.org/pdf/physics/0610030
You can't go even close to c. Even as 'low' as 0.3c could be dangerous. This limits the number of stars, which might have suitable planets even more.

Do you really know what you are talking about? Building generation ships, which are big enough to have a large enough population to build a genetically stable society? For a travel, which takes several thousand years? 100% self-contained for such a long time? To a planet, from which we get information, which are several thousand years old? Oh, I am sure there would be many who would sign for such a ride. Might be even fun for a while, but don't expect that any descendant ever reaches such a planet alive. But hey, the way is the goal.

It would be pretty cool if life in general could outlive this planet. At the moment all life that we know about will die when this planet falls into the sun.

First we were alone. Other planets? No way. Then we discovered: Hey, other suns have also planets. First we were able to see only the biggest ones. Now we can detect smaller and smaller ones. Planets almost seem to be something very common. Life? I really would not worry, that Earth is the only planet with life.

Mars? Jupiter moons? Finding one might be nice, but reaching one without ftl? Very unlikely.

Probably way more realistic, than finding one and getting to it.

So, we will need it. Very funny. What do you intend to do, when we find one? Buy a bus ticket?

I just don't understand what problems you have with what I wrote. Did I say that I advocate 3D printer regulations? I don't. First I don't see that it can be regulated, second... I want to have one of those myself. Not to print guns, but all the other cool stuff. But a problem does not go away just by ignoring or denying it. Even though I am constantly told here how easy it is to build a working weapon with stuff from a hardware store, it is not easy. Not many people are skilled enough to build their own weapon from scratch. At least not many compared to the numbers when in a few years in almost every home such a printer stands. Unlikely? How many homes had a 2D printer 30 years ago?

Don't think so. Generally yes, something like this will happen. But at the moment such printers are far too rare as that the usual protection mechanisms are lobbied in.

Cunt.

Not necessary to sign a post here with your real name. 'zedtwitz' is doing fine as nick.