SubversiveBox is a project mainly written in ..., it's free.
Automatic, Dropbox-like filesystem-watcher for SVN
SubversiveBox
SubversiveBox brings all the Dropbox-usability-goodness to plain old SVN repositories. Start SubversiveBox on a working copy to let it automatically commit changes, new files and folders and deletions to your server, so you can focus on working instead of submitting.
Usage: SubversiveBox.exe
or
SubversiveBox.exe <folder to watch> <SVN username> <SVN password>
Caveats: SubversiveBox does not support the renaming of folders at the moment (something which you shouldn't do in a working copy anyway). To rename a folder, please stop SubversiveBox and use SVN's 'rename' command.
Also, SubversiveBox is very early alpha-software: Use it with caution and always make backups of important files.