At first I thought it was one of those e-mail scams: "You won 2 million dollars," or some equivalent. However, the amount was a lot less, and it seemed so... legit.
I did some research, remembering that indeed, I had done a survey like that, and eventually responded. And voila! I actually did win $200 to spend at Amazon.com.
Ooooh, now what? I'm going to buy stuff that I would otherwise never get, but that I really want! Suggestions are welcome.