Mark Diller has an article on gameinfowire.com explaining how to move files from TiVo to your Sony PSP or computer. In the interest of fair use, Diller also explains how to circumvent the DRM that protects TiVoToGo files using DirectShow Dump. Snippets:
Step Two: Strip the DRM. TiVoToGo files are wrapped in digital rights management (or DRM) software that keeps you from sharing those files indiscriminately with your two million closest friends via the Internet. Of course, you’re not doing this so you can share the file, you just want to watch the program on your PSP, and this falls under the heading of fair use (or at least it does for as long as fair use still exists -- contact your local Congressman and encourage him not to introduce legislation that will take that right away). To play the file on your PSP, you first have to get rid of the DRM wrapper. You can do that by downloading a free utility called Direct Show Dump. That utility will convert a .tivo file (which must be played with Windows Media Player) into an mpeg that can be played with a variety of software on most any device.