OriginalJoeCool
Tech Monkey
I'm leaning toward Linux now. I found a book on cross-platform development: http://www.amazon.com/Cross-Platform-Programming-Charles-Development/dp/1584503793. It covers development for PC, Mac, XBox, Playstation 2, and Gamecube, I believe. It is very thorough, while perhaps a teensy bit outdated (published in 2005).