November Calling

http://www.novembercalling.com/

Using a giant phone tree, committing to make 5 phone calls can deliver
hundreds of votes - whether or not you live in a swing state. In 2000, 50
million registered voters never made it to the polls (and more of them
supported Gore than Bush).
Here's how joining the November Calling phone tree works: it's free, you
won't get spam, and you don't have to give a lot of personal info. Just:

Promise to show-up and vote against Bush/Cheney
Promise to make reminder-to-vote calls right before the election to a
realistic number of likeminded friends and family members
To make a bigger impact, ask everyone you're planning to call to join the
phone tree too, and then keep spreading the word.