You have to refer your friends to this one, but you only need 5 for a prize.

Get freebies from Distillers List for referring your friends. Sign up and send your link to your friends.

Refer 5 Friends – Free Shot Glass
Refer 10 Friends – Free $10 Gift Certificate
Refer 25 Friends – Free DL Copper Mug
Refer 50 Friends – Free Mug, Gift Cert, and Shot Glass