Do you use MBS Plugin?
We have a lot of functions for Events/Reminders.
or see this
There are many ways to do this. Apart from the MBS route, you will find others if you Google using the terms ical filemaker.
Some which floated up to the top of the list were:
iCal can be integrated with AppleScript but it is not without it's quirks. I've found it somewhat limited.
I'd recommend setting up a Google Calendar, share this with iCal users and use the Google Calendar API to create and modify events. ( you'll need to set up a developer account and some other stuff to use it ).
Two way syncing is possible with some extra work.
Maybe this link could get you interested:
It's a free demo by Mike Phalen and uses also a free BaseElements Plugin for the OAuth and http calls.
I think the answer to the original question is simply: Yes
Different ways are possible, but for that we need to know details.
e.g. what should sync (reminder, calendars, events?), in which direction (just push to people from FM or get changes back?), should this run on one Mac for all or on each of them?