Show items on certain days?

That’s a nice interesting problem.

The simplest / quickest / cheapest way I can think of is to add a custom-meta called e.g. “visible_days” to relevant products and enter something like “YYNNNNN”. Then I would write a cronjob script to run at the start of the day that would use this data to “manually” change the post_status of the product to “published” or “draft” as needed.

Thanks, Whitelamp. I’m more of a front-end guy; do you have any guidance on what the script would look like?

Sure, from your point of view it would mostly look like an invoice <grin>. But seriously, any half-decent programmer should be able to write a script based on the above description. (Hint: I’m at whitelamp.com). The only question really is whether to write a “real” cronjob and fiddle with the database directly or write a “proper” plugin that uses wordpress’s own cron functions and post status manipulation functions. I’d guess the second way would be more robust in the long run but possibly more expensive.