America should take up the metric system.

Speaking of crazy ideas.... sitting around Googling methods of terrorism may not be the best way to stay of the CIA's watch-list.

That was sort of my point. Most people are going to imagine it as a more perfect world. But if they were to think through all of the implications, they would see that it probably involves massive taxation and a very very strong central government, with less motivation for people to do dirty and difficult jobs.

They want something they can't, or don't, accurately imagine.

Most people can't imagine what a world without ageing would be like, and they can't want what they can't imagine.

I have to agree with Lumifer -- most people can imagine (and want) a world without aging, because they would not bother to think about the demographic trends. I would compare this to asking someone to imagine a world in which no one was living below the average income level; I think most people would agree that this is easy to conceive of, and desirable. It's only the select few who would think this through and wonder how the powers that be are going to achieve this without doing something very drastic to a lot of people.

Your real world clone would take 20 years to "make" and be a separate person, like you would be if you grew up when they did.

This is partially missing the point. The goal is to make a separate body, compatible with your biology. There is no need to grow a clone with a functioning brain -- any medical science sufficient to clone a human would be able to clone an acephalic human (WARNING, NSFL, fetus with head damage), and growing a clone with a fully functioning brain (i.e., not driven insane by being grown in a de facto sensory deprivation chamber) would be much more expensive, even if you kept education to a minimum.

Still, all this is ethically questionable, something that would need a lot of advance planning, and will be a long time in the future. It is true that fixing your body piecemeal will almost surely be a better option -- even if it does end up involving some limited form of cloning organs.

This is consistent with 27chaos's statement, though. If you get a body transplant at 65, you have solved a number of medical problems, and the chance of living the next 30 years without having to worry about Alzheimer's is ~70%. Of course, Alzheimer's disease accounts for only 60-80% of cases of dementia. But still, I think there would be a market.

It is also worth noting that cardiovascular factors, physical fitness, and diet contribute to the risk of dementia, including Alzheimer's. These are not the greatest risk factors (as you might have guessed, age is the greatest risk factor), but these can be managed if you are motivated to do so -- in fact, getting a new body should be a fairly effective way of managing cardiovascular fitness.

From the Freakonomics blog: "FDA prohibits any gifts to blood donors in excess of $25 in cumulative value".

Various articles give different amounts for the price per pint that hospitals pay, but it looks like it's in the range of $125 in most cases.

I'm not sure where you got the 3 month figure from; in America we store the blood for less than that, no more than 6 weeks. It is true that the value of your donation is dependent on your blood type, and you may find that your local organization asks you to change your donation type (platelets, plasma, whole blood) if you have a blood type that is less convenient. I do acknowledge that this question is much more relevant for those of us who are typo O-.

I think you are often right about the marginal utility of blood. However, it is worth noting that the Red Cross both pesters people to give blood (a lot, even if you request them directly not to multiple times), and that they offer rewards for blood -- usually a t-shirt or a hat, but recently I've been getting $5 gift cards. Obviously, this is not intended to directly indicate the worth of the blood, but these factors do indicate that bribery and coercion is alive and well.

EDIT: The FDA prohibits any gifts to blood donors in excess of $25 in cumulative value.

It is also worth noting that there is a thriving industry paying for blood plasma, which may indicate that certain types of blood donation are significantly more valuable than others (plasma are limited use, but can be given regardless of blood type).

"Chalmers argues that since such zombies are conceivable to us, they must therefore be logically possible. Since they are logically possible, then qualia and sentience are not fully explained by physical properties alone."

This is shorthand for "in the two decades that Chalmers has been working on this problem, he has been defending the argument that..." You might look at his arguments and find them lacking, but he has spent much longer than five minutes on the problem.