I am primarily a Subversion and Git fan these days for my source control needs, but before them I did use SourceGear's Vault as a personal solution for my source control needs. A single personal license of SourceGear's Vault was free and I suspect it still is today. In fact, I also used DiffMerge for awhile as well, which is a free diff tool for comparing file changes with the intent of merging the changes, etc. :)
Having used and enjoyed Vault up until I started using Subversion, I wanted to mention that SourceGear just released Vault 5.0 and Fortress 2.0 if you are looking for version control and possibly application lifecycle management for your teams. Subversion, Git, and TFS are not for everyone, so it is good to know that other version control and source control solutions exist.
The best place to go for more information is the SourceGear website. I would check out the Development Blog here which highlights the new Vault 5.0 and Fortress 2.0 release and go from there. There is a free 30 day trial that might be worth trying.
Check out other .NET Developer Tools, Code Generators, and O/R Mappers.
David Hayden