Sign up here and complete your profile and then check your "My Profile" page to see if you have any offers.
I signed up (it's free and took me less than 3 minutes to do so) and immediately received an offer to try a full-size bottle of VitaCraves. Many others are also receiving this same offer when they sign up right now. So if you have a few minutes and like to try products for free, it's definitely worth signing up for!
This is very similar to BzzAgent.