Thomas Friedman has spoken out for the need of a third party. At the Aspen Ideas Festival, he said, "We need a third party. I am for a third party. We are trapped in a corrupt duopoly". See "Has the Third Party's Moment Arrived?", John Avlon, The Daily Beast, 2011-07-01.
He also said, "One thing about the Internet and the hyperconnected world—it has flattened every hierarchy in the world from The New York Times to the banking industry. It’s flattened every hierarchy in the world except the two-party system, and that will not remain. That is a prediction that I will make."
This reminds me of the aphorism, "Are you part of the problem or part of the solution?" And of course, I have to preach, probably to the choir, be sure to vote in each and every election. If you have no choices that you like, write somebody in.