I think I've found a way to sync OF at home to Outlook at work
 

Here's my setup

Work PC:
Outlook with GTD plug-in
Sync to Windows Mobile handheld

Home Mac:
Missing Sync for handheld to iCal
OF-iCal sync

-Tasks created in Outlook have the category set the same as the context. The contexts come into iCal as separate calendars.
-Tasks created in OF sync to the corresponding iCal calendar