Jake over at blahstuff alerted me to the JavaHMO I had heard about a few weeks ago. Check out the screenshots to see what new functions this open source, free piece of software adds to your Series 2 TiVo. I imagine it's a rewrite of the HMO server that exploits features in the developer API and lets set up schedules to download images of weather and movie data from the web.
Jake also said it was a cinch to install and configure. Hopefully TiVo takes notice and rolls similar features in (and doesn't send the JHMO guy a cease and desist :). Looks like it's linux and windows only for now.