Legit ways to earn M$ points?

[breakpoint]

Before anyone says it, yes buying them is the easiest way. I don't have the funds to do so and only need 400 to buy the track pack that just came out for Trials HD. I used a site about 2 years ago and had to do things like surveys and such, but it worked. I tried to find the site but can't remember the name of it and don't see anything familiar when looking at sites. Does anyone know of a site like this that I could earn some M$ points?