You can give blood. There was a shortage anyway (it happens a lot in the summer), but with the destruction and lack of power in hurricane-affected areas, the shortage is that much worse. Wherever you are, you can help.
I walked the talk, people. Yesterday I made a special trip into the city (BART *and* the bus!) and gave blood. I was heartened to see that the blood bank was very busy--and ashamed to see from my card that it's been five months since I gave last.
Later today, I think I'm going to drop some petty cash at my local Salvation Army store, and get off my ass and list some books and DVDs on half.com, to turn some stuff back into money to donate.