I used desktop calendar to show me a calendar, however it doesn't sync with iCal. One I used to use was menucalendarclock - it sat in the menubar, with a dropdown calendar, which you could add events to. Not sure if it simply launched iCal to add the event or if you could do it within the menu itself. You should be able to find it at versiontracker.com or macupdate.com
Even just a search for calendar turned up some more results when I did that just recently. The one I mentioned was shareware, but there may be a freeware alternative.
Something a little different - there are live updating desktops from Vlad Studio, which were discussed a little in the desktop of the month thread. There's an app you launch to run them (also available from the vlad studio site) and a large number of free desktops to download with it. Others require membership, but there are some pretty good free ones. All desktops show date and current time in them.