Earn free steamgames with Getting achievements!
How does it work?
You sing up and plaly falashgames, if you get any achievement you will get points. 
If you meet the treshold you can get steamcodes to exchange for steamgames!
achievements usually pay 15 points, and most games are 300.
Some games have over 5 achievements so I dont think it is hard to get those achievements!
check the link for more information or sign up directly here: http://bit.ly/1f8REPc

blogger:
http://www.freesteamgameswiki.blogspot.com