Windows Source Control for the Lone Developer?

bitFlipper asks: "I'm the sole developer of embedded software for a small company. Currently I'm maintaining about five different product lines, each with about 30K lines of code and 100+ files. At the moment I'm winging it without a version control system (using snapshots to CD-R), but this is an unhealthy state of affairs. The open source/big project model of many developers scattered across the globe doesn't apply here--it's just me. And since I have to provide my own tools, the budget for this is near zero. It also has to run on Win32. Oh, and the code I'm developing is not open source. I've looked at RCS (which is certainly simple, but maybe too simple) and Subversion (which is probably overkill). What can people recommend for a version control system that's free or low cost, Win32 compatible, and simple to set up, use and maintain?"