Concurrent Versioning System (CVS)

CVS. It's kind of old, but it works. I don't know what I did before I learned versioning software.

There's a good list of links to relevant software over at http://www.wincvs.org/. This includes CVS server and client software for Windows and Linux. Also, links to some merge and diff tools.
Currently I'm having good luck (i.e. easy enough for a dumb guy like me to figure out) with tortoise cvs.
- Quick tortoise + pageant note: use SSH2 keys. SSH1 didn't seem to work
To apply a .diff file (created from diff, in Unix) use 'patch' - there's a usable windows port from djgpp
To remove all those annoying CVS folders:

List the folders from the Windows command line:
for /f "tokens=*" %i in ('dir /b/a/s CVS*') do @echo "%i"

Delete: for /f "tokens=*" %%i in ('dir /b/a/s CVS*') do @rmdir /q /s "%%i"
Or, the batch file:
@echo off
echo Deleting CVS folders and files under: %1
REM Open Folder specified by parameter.
cd %1
REM Recursive delete command
for /f "tokens=*" %%i in ('dir /b/a/s CVS*') do @rmdir /q /s "%%i"
echo Done!

From http://www.danieltome.com/blog/2007/01/13/delete-cvs-files/

tags: cvs, concurrent, version, recursive, diff, merge, winmerge