Fribiz is a website just like Lockerz with the only difference that it's cooler. You get points when you signup and for every cool activity you have on this website.
The prizes vary from iPhones, Apple iPad's to PlayStation and different 25-50$ gift cards like Nike, Foot Locker, Zappos or Amazon. The best part about Fribiz is that they give your points back after the auction ends and even more they compensate you with some extra points for your efforts.
Practically you cannot miss the chance of winning prizes.