Personally, I believe in democracy, and I think that the only legitimate governmental power comes from the people.
However, I am also sympathetic to the argument that our democracy is nearly a total sham designed to maintain control.
As far as wheather or not to vote though, I think we need to think through this with a bit more of the complexity the issue deserves.
I have decided to abstain from voting in presidential elections and most congressional elections because I think the process is a sham, I don't really feel like I can support any of the available canditates, and I don't want to lend my support for these elections by taking part in them.
I think if you vote for president, even for Nader you are in effect saying 'I agree with the method of this election and I have had my legitimate say, so I am bound to accept the outcome and consent to the legitimacy of our president.'
I also think that not voting--to keep the turnout low--has the potential to actually weaken the government because it can be used to challenge the legitimacy of power.
For example, when Clinton tried to pass universal health care in the early 90's he claimed that he had the mandate of the people since he had been elected on a platform that included this issue. However, the media (or the pharmaceutical companies--you decide) jumped all over him and claimed that voter turn out was low and he was elected by a minority (becuase of Perot) and thus his mandate was weak; consequently, his healthcare plan died.
On the other hand there is the question of voting in local elections and for referendums and ammendments. On these issues I cannot come up with a legitimate reason to abstain from voting.
I recently moved to Oregon from Virginia, and I must say that most Oregonians I have met seem to take for granted the incredibly vibrant democracy that exists here.
Just look at the number of canditates from non-major parties for state office and the number of ammendments up for vote. Think also about how the ammendments can challenge the power of BushCo. to control our country (for examply look at medical marijuana or death with dignity issues that have directly challenged the ability of the federal govt. to exercise power).
I know there are problems with even these elections and that in many cases corporate money has way way too much influence over the outcome, but is that alone a good enough reason to abstain? I don't think so. How else do we challenge the power of these corporations if not by thinking for ourselves and voting agianst their interest. Otherwise I think we are just giving in.
I believe in democracy, and I believe in voting in legitimate elections (or at least ones that are not complete shams). How else do we effect change in the power structure absent of a real revolution (which is not going to be accomplished by ideologues ranting on indymedia or spray painting trashcans).
I guess ultimatly what I'm saying is that some elections do hold the possibility for real significant change and I think it is shortsited to dismiss all elections under the same ideological umbrella.