I have Ubuntu on my laptop.
You can run quite a few games, and if you know what you are doing then you can use wine and things to run windows games.
Nothing else to say, because everyone else has said the things I wanted to say lol.
I've tried it at a few different occasions but as I'm not such a wiz with linux-based OS's I couldn't really do much with it.
As a free OS it's great but I personally had no luck with either games or the apps I want on it.
Such as the Adobe Creative Suite.