In the episode of the Simpsons Treehouse of Horror VII, you can find one of the most poignant cultural references ever made by a cartoon:
Homer: America, take a good look at your beloved candidates. They're nothing but hideous space reptiles!
Kodos: It's true, we are aliens... but what are you going to do about it? It's a two-party system; you have to vote for one of us!
Man1: He's right, this is a two-party system!
Man2: Well, I believe I'll vote for a third-party candidate...
Kang: Go ahead, throw your vote away!
Of course, Ross Perot is then show punching a hole in a "Perot '96" hat.
So, let's say that you aren't completely happy with either Democratic President Barack Obama or Republican Candidate Mitt Romney. What's a budding protester to do?