Open Source Calendaring system.

[EmperorIQ]

Does anyone know of a good open source calendaring system which helps keep track of deadlines, schedules, dates, etc.?

It has to be expandable, easy to maintain and written in either php or asp, asp.net. I know I can google, but I would like some input on user experience.

Thanks

 

[screw3d]

I know it's not written in PHP or ASP or web-based, but have you heard about http://www.mozilla.org/projects/calendar/sunbird.html? I haven't tried it myself though