Expiring Products, is it possible?

First off, just want to say thanks for all the effort put into Zen Cart development, support and all the addons.

I am currently working on a cart that where one some of the products will be spots within a classroom at a certain location at a certain date. Once the date of that event passes it's obviously moot to try and buy that product anymore. I was wondering if there's a way to allow product to expire after a certain date/time. I've been browsing around the admin and haven't found something to solve this (there's quite a lot to go through) and have also searched the forums and found this:

http://www.zen-cart.com/forum/showthread.php?t=12633&highlight=expire+items

But haven't come up with a solultion yet. Any pros out there with some words of advice?

Thanks,

You could look at how featured and specials are managed and add a products_date_expires field and incorporate a similar logic to update once per session ...