Free Indie Games
I love to support indie games. Indie developers aren't afraid to take a new idea and run with it. Most of the time I find cheap indie games on steam or my ipod touch to try out. There are all sorts of free demos on both services and a full copy of an indie game is almost always under twenty dollars. Many are priced around a buck.
If you aren't afraid of wading through some bad games the other option is to play flash games online. The amount of free games online is amazing but finding high quality games can be a challenge.
This is where Kongregate comes into play. It's the best flash game site that I've ever found.
Kongregate has a rating system to help filter through all the junk games. The community rates games and the site lets me sort by top rated and most played. Every gaming distributor needs to be able to sort by rating and being able to sort by number of plays is like icing on the cake. This is one area in which the apple app store is severely deficient, but that's another discussion.
Kongregate even has an achievement system and tracks progress across every game on the site. It requires the creation of a login/password but the system works really well. It's like having the Xbox Live achievement system except that it's for flash games.
So what are you waiting for? Go play free games!