InviteBox, social referral program, allows merchants, bloggers, developers (and anybody else with a web presence) to refer friends and customers to recommended products. Users can take advantage of pre-determined referral offers (e.g. coupons, promo codes, free products, cash incentives, etc.) or create custom incentive programs. InviteBox offers all the needed moving parts from creating the referral program to implementation, and the analytics to measure success. Users can simply insert a widget into a website or utilize the Reward Callback API.
Twitter photo sharing service TweetPhoto is encouraging developers to use its platform by giving them a way to earn some money. The service pays developers by the number of photos that its users upload via the TweetPhoto API.