Saturday, January 20th, 2007
Now there’s a way to put video back to my TiVo from my Mac. The
interface for turning it on is hidden until you either command-click the
TiVo preference pane or type defaults write com.tivo.desktop FileVideo
-dict-add VideoUIEnabled -bool true into Terminal (this feature is
also known as “TiVoToComeback”).

The original discovery came from this TiVo Community Forum post.
Also, you might find TiVoizer useful in converting videos to the mpeg2 format that TiVo likes.
