I took Mark Bucciarelli's vcal.py code, improved and cleaned it up and wrote a simple CGI frontend for it. It's been more popular than expected via my weblog posting at http://cpbotha.net/2007/04/26/google-calendar-to-palm-desktop-conversion/ (which links to the online CGI as well).

In short, you can convert ICAL from for example Google Calendar and convert them to VCAL version 1 files to be imported into Palm Desktop. The whole thing is a web app, so you don't have to download anything, just go to the link above if you wish to convert. I've put the code here for the curious.