Steam is holding a contest of sorts, where if you complete certain objectives between now and December 20, you could win 100 games.
What you do, is head through this link and complete any ten of the objectives listed. Each objective you complete gains you another entry in the drawing, and if you unlock all four posted today, you’ll have even more chances to win.
Once you’ve completed the objectives, log onto Steam on December 20 for your name to be thrown into the prize pot. If you are one of the three winners chosen, pick out 100 game titles on Steam’s dime.
That’s not all though. Every two days, Steam will choose 20 lucky people who’ll win 5 games games posted on their wishlist.
You can also unlock a hat in Team Fortress 2 by completing objectives.
Sounds like a easy way to possibly win a bunch of games for doing what you would normally do anyway, so why the hell not.