MyPoints has been around since 2004 and offers regular paid surveys along with other earning opportunities including shopping, offers and rewards for printing and using coupons. Points earned can be redeemed for gift cards at a variety of stores, Amazon included. They do not currently offer a cash redemption option.
Referral Program: 10% for referrals with a cash bonus for referrals who spend $20 in shopping.
Index: SurveySavvy | ClixSense | InstaGC | SwagBucks | PrizeRebel | YouGov | PaidViewpoint | BrandedSurveys | MyPoints | Springboard America