I've been working with my Axim x30 and found to my annoyance that if I didn't want to set up a sync with my work computer, I had to trigger the guest account every time. A quick search of
Aximsite came up with
this gem: an undocumented Activesync registry key that allows you to set Guest status for any PPC that connects to the computer, no prompting, while allowing partnerships that are already set up to sync as normal. The article is worth reading, as it describes some moderately interesting applications.
Other keys described allow for autostarting applications at device connect and disconnect. Potential uses are described. There is also a tool for setting the keys available for download. This is an old article, from early last year or before, but the keys appear to be the same, cause it's working for me! Recommended.