I've been playing with one that was included on my server. Here's the link -
http://www.k5n.us/webcalendar.php. I haven't put it to use just yet but it
looks like it might work. Gives you the option for public or private viewing.
It also lets you export it to a file for Outlook, Palm, etc. Lots of options
for color layout and Admin control.

Hope that helps!
GJIsh