Calendar Synchronisation Problem

Here's the problem:
My PDA is setup to synchronise my calendar with my Work PC. As my calendar is setup to be publicly viewable I do not want personal items to be synchronised with the PC. Activesync 4.1 no longer seems to allow you to synchronise only certain categories. I see two possible solutions:

1. Find a (free) synchronisation software tool that allows me to synchronise categories separately. However, it must be one that only requires to be installed on the PDA as I cannot install software at work. Does anyone know of anything?

2. I could install a separate calendar program that does not use the Outlook database i.e. the database that synchronises with the PC. Does anyone know of any free ones that would fit the bill?

Or does anyone have any other ideas?

Thanks in advance.