FileBot is the ultimate tool for renaming your tv shows and downloading subtitles. It's streamlined for simplicity and it just works. FileBot supports Windows, Linux and Mac, plus there's a full-featured command-line interface for all sorts of automation.

Video Demo:
http://www.youtube.com/watch?v=zcSFKiwFLZw

Support Forums:
http://filebot.sourceforge.net/forums/

Download (Intel Mac):
http://filebot.sourceforge.net/download.php?type=app
Download (32-bit Windows):
http://filebot.sourceforge.net/download.php?type=msi&arch=x86
Download (64-bit Windows):
http://filebot.sourceforge.net/download.php?type=msi&arch=x64

All Downloads (Windows, Linux, Mac, BSD, Solaris)
http://filebot.sourceforge.net/#download