Dave Zatz at ZatzNotFunny has found a way to use the new TiVo Desktop 2.3 to transcode previously transferred recordings, and to use different profiles that the defaults in the UI. By default Desktop Plus 2.3 only transcodes new recordings immediately after transferring them from the TiVo, and only into one pre-selected format. With this method you can transcode recordings you’ve already transferred, and into multiple formats. You can even use other formats which are in the XML configuration file, but which are not in the selection pull down in the desktop UI. You may be able to make you own profile in the file, but I haven’t tried that. See his write up in his blog. It requires venturing into the command line on Windows, but it is fairly simple.
EDIT: Dave posted more information today. You canedit the XML file and change the resolutions from the default 320×240. So you could set the PSP to 480×272, or the Treo to 320×320, etc. It looks like you can optimize the resolutions for your device if you’re willing to edit the XML. Very cool!