Find $285 Under the Couch

Retweet: $20

This month, American Express started asking cardmembers to sync their credit card accounts with Twitter and retweet certain hashtags (you can sign up to link your AmEx and Twitter accounts here) in exchange for savings from big brands such as Whole Foods, Best Buy and Zappos. For example, on a recent day, if you had tweeted #AmExWholeFoods, you'd have received $20 back on your next $75 in-store purchase—and the offer would have been automatically loaded into your AmEx account, ready to be redeemed the next time you shop at Whole Foods. Another deal: tweet #AmexSeamless5 and get $5 back on your next $25 purchase on online food delivery service Seamless.