Currently the refer-a-friend program is offering free cashback for every friend you refer.

Here??™s how it works:
You just recommend your favorite Vitaminfix.com supplement to a friend and earn Cash Back. For every friend that registers for an account at VitaminFix.com, you receive 250 Cash Back Points. When your friend registers they also receive 250 CashBack Points, and there's no purchase required! Points are converted to cash you can use at checkout or if you reach $50 they mail you a check. And...points never expire.

Once you are a registered user you receive a personalized invite link code. Post this link code on your blog, tweet, facebook, or emails and when someone clicks your link and registers you receive a credit to your account.