I signed up with FreeiPods.com. They are giving away free iPods if you sign up for an offer, and you get 5 other people to sign up as well. They make their money from the referral fee from the companies that give the offers. There are a couple of web sites that have investigated this, and they have found that this is legit. (Engadget story, Wired News)
Here is the link to sign up.
One of the main reasons that I signed up for this was because there was an offer that I was interested in, even without the possibility of a free iPod. Blockbuster.com is one of the offers. We currently are using Blockbuster's Movie Pass, so we can keep 2 movies out for about $25 a month. Blockbuster.com offers a similar service to Netflix.com, but they have a plus. With the Blockbuster.com service you can rent 2 movies a month for free from the Blockbuster store. All of this cost only $17.50.