Sent.
VCS? Like, variables? Or very cool scripter. :P
Version Control System, like
Mercurial (aka hg) or
Git (no, not the insult). Both are free.
For hosting you can host yourself (requires some work to set up) or use a "public" hosting site. The biggest sites are
Bitbucket (for Mercurial) or
GitHub (for Git). Both are free for public repositories and Bitbucket also provides free hosting hosting for teams of up to 5 people. For private repositories GitHub limits both how many you can have and how many people can access your private repositories in total (although each person is only counted once) while Bitbucket only limits the total private collaborators.
You can also access remote Git repositories from a local Mercurial install using the
Hg-Git plugin by GitHub although it's quite buggy and the fact that it conflicts with the
Kiln "client"'s extra bundled plugins.
For you learning Mercurial would probably have the biggest benefit as "Modders Corp" uses that as well. Also, IMO Git has a steeper learning curve.
Disclaimer: I am a Mercurial fanboy.