Not that I know of, but I'm sure you just gave some developer an idea for a great app.
I can think of one work around: use a spreadsheet along with iCal. In the spreadsheet you can keep track of exactly what you need to send or will be receiving. Then, have iCal give you a message and perhaps even send you an email (though I know you're trying to get away from this - it would be just a backup measure) when you're getting close to the date (maybe even set up alarms at different dates, e.g., getting close to the date; closer; dude, you gotta send it!). You could probably do this just with iCal, but you can fit more information in a spreadsheet.
Just a thought. Good luck!