"I am a black South African, and if I were to change the names, a description of what is happening in the Gaza Strip and the West Bank could describe events in South Africa."
~Archbishop Desmond Tutu

Global Exchange has tons of info on what we can do, and a list of US Companies that operate there.

Money talks -- loudly. If we can't affect our government funding them, we can stop our own funding of it.

You've gotten the email, or heard about it in the checkout line, or around the water cooler. "Don't Buy Gas On May 15!!" it sez, with much ranting and pent-up fury and a, sadly, entirely fictitious claim that "this was done in 1977 and gas dropped 30 cents the next day!!" and the like.

Hey, I'm all for it. Not because it will bring down the price of gas though. Nothing will bring down the price of gas except a reduction in the consumption of gasoline in this country. But the call to arms for the Ides of May is still possessed of some merit if only because it gets people talking and thinking about the subject.

Boycotts are not as hopelessly eye-rollingly futile as people would like you to believe. Collective action is never wasted.