Last week, my friend "Don" and I were discussing a web contest held by an ex-Googler startup. The top prizes are Kindles.
Me: "I'm going to lose. The contest page actually features my profile, but I'll lose."
Don: [visiting the page] "What's the judging criteria? Number of reviews written? Seems that would encourage spamming."
Me: "Yeah. I actually spent time writing witty content, but I was quickly overtaken by people who wrote over a thousand one-sentence reviews."
Don: "It's okay. I'll buy you a Kindle."
Don: "The Kindle will be for winning my contest."
Me: "What's your contest?"
Don: "Most Awesome Friend in the World."
Me: "Oh. [momentarily happy] But... due to extrinsic motivation, that'll make me want to be your friend less."