Comment GitHub (Score 4, Informative) 69
If you are making the repositories public, GitHub is the way to go. You only have to pay if the repositories are private. It gives you the ability for people to send pull requests for changes (which you can choose to accept), issue tracking, etc. The pull request system is really nice, because you ultimately have control of what gets pulled into your project, but anyone can pull it down. It's pretty much the standard hosting, and works across all platforms.