Application for downloading subtitles for your movies and tv episodes using OpenSubtitles.org.
The searching is done by calculating a hash value for every movie file and then looking in OpenSubtitles.org's database for matching subtitles. This way you find matching subtitles quickly and can be sure they'll be correctly sync'ed with the video.
Undertext is made for Mac OS X using it's Cocoa so it integrates very well with the system. Undertext is very simple and intuitive to use and install. Compared to using the browser this is a very quick and comfortable way to get your subtitles.