Folder-RSS is a simple program that scans folders on your hard drive, looks for new files and then makes an XML file listing the results. I wrote it so that Xbox Media Center would list the latest TV shows I had downloaded in its ticker. If Folder-RSS is not running on the same machine as XBMC then I recommend you use it in conjunction with the excellent Dropbox so that the resulting XML file ends up in a place where XBMC can find it.
Folder-RSS is fairly configurable. It will sit in the tray and scan your folders in user-definable intervals using multiple filepatterns. It also has an intelligent renaming feature that will present my.show.s06e12.hdtv.xvid-2hd.avi as my show s06 e12.
Perhaps you can find other uses for my program. I hope so! Let me know about it by mailing me.