TiVo Desktop 2.6 adds video transcoding, folder monitoring in March {Engadget HD}

Mar 18th 2008 2:35PM Check out pytivo. It's an open-source alternative to Some tinkering required, and it's not perfect, but it will run on anything that has python & ffmpeg (both of which are available for your mac).

http://pytivo.armooo.net/
http://tivocommunity.com/tivo-vb/showthread.php?t=328459