GIT

Git is a configuration management system.

See http://git-scm.com/ for more details.

The nice thing about git is that there are various kinds of repositories. A given zip file can contain both the current working state of a project and also the git files describing all previous versions. You can then pass everyting of interest about a project around in one big old zip file.

On the other hand if you want to have a shared repository for developers around the world, you can set that up as well.

Git is a bit wierd, but for most common single branch development activities, it works great with trivial overhead.