[H] Networkable ToDo List/Calendar

[Thane Sherrington]

I'm looking for a good, simple, lightweight program that will allow 
me to share to do lists and calendar information on a 
network.  Preferably open source.  Any one have any suggestions?

This is the sort of thing I need to track:
Appointments
Phone calls that need to be returned
Tasks that need to be completed (start and end date for tasks would be nice.)
Recurring tasks.
T