I have a few invites available for moola.com, an ad-supported site that gives you a penny and gives you chances to double your money repeatedly by watching an ad and playing a head-to-head game. Leave comment with your email address if you're interested.
Currently it is in Beta and registration by invitation only.
Update: I received 4 new invitations so I now have a total of 5 available. So just say the word and you're in.