Ebates is a nice little shopping site. If you shop using links from Ebates you can earn a cash back bonus. Another advantage is they also have coupons and coupon codes to use. If you already shop online, log into Ebates first and earn on the purchases you already make at Amazon, Walmart, Ebay, and more!
They also have a Refer-A-Friend program. You receive a $5 bonus for each qualifying friend. (They need to make a qualifying $25 purchase). Occasionally they offer bonuses beyond the $5 bonus too!