I just bought 15 computer games. Some of them are different versions of the same one, so it's more like 12. The reason that I got them was so that I could look at the source for them. I bought the "Valve Complete Pack" from VALVe through Steam, their program that makes sure that no pirate copies of their games are made (it obviously isn't very effective. Prior to buying these games, I had a not-so-legal version of Half-Life 2. The fact that they let you see the source is what made me buy it.