They say misery loves company, so it's interesting that
Microsoft really wants its Xbox Live! customers to get their friends to sign up, too. I'll give you time to think about
that one for a second. The terms of the deal are laid out in the link. The gist of it is that you get free games for
every friend you refer (up to five games —which shouldn't be a problem since none of us have more than two
friends).
Engadget
TUAW