I just bought a "today only" deal after it had apparently expired. I added it to my cart before the "today only" page had been updated, but purchased after.
I've often been able to add things to my basket from Scan's "Today Only" deals and go back several days later to find them still in my basket. I can then go all the way to checkout, but haven't actually purchased anything from previous "today only"s (except for today) so can't confirm that they always stay at the reduced price, but don't see why they wouldn't. CAN SOMEONE ELSE CONFIRM MY SUSPICIONS?
When you click "buy" on a today only item, it adds two entries to your cart - one with the product code and description but no cost, and another with just the description reduced cost. If you don't empty your cart, use the same computer and (I presume) don't delete your cookies, both "items" remain in your cart indefinitely so you get the reduced price!
Worth a try for anyone who doesn't have the AVforums discount delivery and would rather only pay one delivery charge after selecting several of Scan's best offers...
One other thing! Your account details and delivery address etc have to all be previously entered though or it clears your basket when you update them.
Hope this helps...