This is a simple AppleScript droplet which includes a binary of the TiVoDecode program. Just drag and drop your .tivo files on it and get an MPEG-2 video out. You can then use other tools to convert that MPEG-2 into something else.

Documentation is included. If you need help getting your .tivo files onto your Mac or converting MPEG-2 files into something more useful, try Google. Problems with the decoding (such as missing audio and other weirdness) are best addressed on the tivodecode sourceforge page. I will not be supporting this program beyond the functionality of the basic AppleScript wrapper.

UPDATE 9/07: There is a great open-source alternative to this little script that is, really, a lot better. Take a look at TiVo Decode Manager.