Here are a few, I think some are free

I researched a bunch and settled on Visual Protect. It's certainly not perfect, but it seems to work so far. And it's easy to use -- no additional code necessary. Regards, Nick Hodapp / CoDeveloper

I agree with this entirely. At least, it's happened to me before

George -- thanks for plugging WorkspaceEx. I'm glad you like it :) But you didn't give the link to your own site! Everyone interested in using CVS with Visual C++ should check out http://www.geocities.com/kaczoroj/CvsIn/