I went ahead and threw my vote in for Nader, for two reasons:
1. Living in Massachusetts, Kerry's going to win the state anyways, and get the electoral college votes, so I feel like voting for Bush here would be throeing my vote away; but if Nader gets a certain amount of votes, it helps lead to the acceptance of a third party in politics, which would lead to a better political landscape than our current one, where most people have to vote for the lesser of two evils.
2.I like cheesing off the hard core partisan people who think you have to live your lives according to the party lines.