It's time to put my flash stuff into proper source control. There are three pretty good options that I've used before. Microsoft's SourceSafe is already on my computer (legally, I think), but it's kind of famously bad. Subversion is open source. Perforce is good and doesn't have a licensing fee for the first two users.

I went with Subversion once I figured out first that you don't need to run a server to use Subversion on just one machine. Also, the app TortoiseSVN integrates Subversion with Windows Explorer nicely.

It took a few hours of fiddling around to get my repository the way I want it, but now it's all set up. C:\svn is the repository, and C:\trunk is my working folder (the little check marks by the files tells you it's working.)

There's a good free O'Reilly book on Subversion, but really the TortoiseSVN documentation is a better read and includes everything I need to know about Subversion for now.