I wrote a script to manage something like a GTD style tickler file in iCal. Basically, it will look for a folder named with today's date (e.g. "September 17") and, if such a folder exists, reveal it in iCal. I use this with a Calendar Group called "Tickler", which I usually leave hidden. In the group are a bunch of calendars named by date. An event runs nightly, triggering the script in the event's alarm -- the next morning the notes for that day are visible. It's a bit of a hack (iCal's scripting support appears to be rather limited), but I'd love feedback. Docs (such as they are) are in the comments in the script.

http://www.faisal.com/software/tickler/AutomaticTicklerRevealer.scpt.zip