Just a link and a note to a GUI and CLI client for CVS repositories.
CVSGui
They also have diff tools, and other CVS GUI tools.
They have tools for many platforms including Windows. Heck, they even have Mac tools!

Note: I front-paged this because I see many people who are primarily small scripters and small project people that NEVER use source repositories and don't know the value they have.

"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!