Has anyone ever heard of this site? You complete offers to earn coins and spend coins on pc games, gift cards, in-game items, and some other things. So far I got portal 2, minecraft, psychonauts, FEAR, and a few other older games, not to mention a bunch of tf2 items.
I found the trick to getting coins without spending money or giving out personal information is to complete all the download & install offers. The problem with these is that while tremorgames itself is safe, the offers they link to more than likely include malware. But I use sandboxie and haven't been infected yet so I recommend that or a virtual machine.
So yeah, just thought I would mention this. A site that actually gives free games without demanding your credit card or completing surveys. Of course there is a little work involved but it really doesn't take long to earn 20k+ coins, enough to buy the most expensive games they offer.