Making a choice between Bush and Gore is like telling the pickpocket which hand, left or right, to use to lift your billfold.
A vote for Nader is not wasted but is useful in two ways:
A. He could presumably (a real longshot here) carry a state or two, enough to prevent an electoral majority by either of the other two - and wouldn't that just shake things up to a fare thee well, or, more realistically,
B. He could get enough of a plurality to allow the powers that be to cease to ignore him next time around.

Posts here seem to regard the candidate of choice to be the lessor of two evils. So if you want to look at yourself in the mirror, please vote for the candidate who most closely mirrors your own feelings and views. If that happens to be Nader, then please vote for him. You will have done the right thing and will know that you have made an incremental step to, just maybe, getting some positive change here over the long run.
MarkS