This post on the dropbox forums says exactly what to do: you can either install an old version of dropbox (I couldn’t figure out how to make it run properly in Linux), or you can use that guy’s Python script. He even provides a Windows binary.
To use the script in Linux, note that you have to change a few lines to manually input your dropbox.db file loation (since the APPDATA variable will not be set). Also, when entering your new dropbox location, don’t use a trailing slash. It worked perfectly for me; now I have Windows and Linux syncing from the same directory!
