Gathr.com is currently doing a promotion where if you refer another person and they sign up, you both each get a $10 Amazon Gift Card. You can build your own package for things that you want, and the monthly fee depends on what you want to receive.
I currently pay $20 a month, and I receive:
$10 Amazon Gift Card
$6 Amazon Gift Card
$10 Toys R Us Gift Card
IGN Prime Membership
Up to 8% cash back w/ Priceline
I can only do this up to 5 times. If anyone would like to sign up, feel free to PM me with your email.