I think what GFK_of_xmaspast is saying is that, even if you think that all (remember third party!) Presidential candidates are equally bad, you should go vote for the other things on your ballot. Local/state initiatives, local representatives, etc.

Honestly, in many ways, those are likely to directly affect you _way_ more than the President anyway. Most (all?) states will let you leave parts of your ballot blank; just don't pick a President if you don't want to.