Cory Doctorow makes a really sensible suggestion right here, that I think every comics publisher should immediately implement.
This would have instant great benefits for me. I don't know about any other POS system, but MOBY has a space on the Individual Item display page (that shows me the sources I can buy a book from, ordering information, price, every transaction I've ever made on the item and so on and so forth) that displays the covers.
Currently, that image defaults to the item code on the Diamond website, though it can be edited to show another source. The problems are three there: 1) Diamond, of course, has to carry it, 2) You have to log on to Diamond's retailer site, which autologs you off after 30 minutes or so, and 3) Diamond is VERY liassez-faire about what size image the put in the standard path. Sometimes you get postage stamp sixed pics, othertimes the largest possible version where the window can only display the first quarter or so of it.
I use the feature ALL the time when people ask about something I don't have. Especially because, in comics there are TONS of "variant editions", and titles starting over with incredibly minute naming variations, and so on, so pinpoint THE thing someone wants to buy is really important.
An ISBN and UPC directory would be VERY helpful, and, besides the whole "having to rename the files" thing, is something that really COULD be implemented "tomorrow". It's just too simple and easy and smooth of an idea.
AND IT WILL HELP SELL MORE BOOKS.
It would also be of great use to me both as a blogger who is basically stupid when it comes to html -- I never ever have art in my posts because I'm pretty dumb about how to do it. This idea would make it trivial.
It would also be of HUGE use to me in putting together ONOMATOPOEIA, the store's print newsletter. CEO (as we call it) has to be out at the same time as PREVIEWS so that we have enough time to collect orders from people properly. But only a handful of publishers actually have publicly available art BEFORE PREVIEWS ships, which is when I need it the most. (Fantagraphics wins the prize here, they have a FTP site with art up, typically, 6 weeks before PREVIEWS ships -- that's a fantastic lead time)
ANyway, I think this is a stupidly good idea, and I urge any publisher reading this blog to immediately implement this idea (though we'd need to add UPCs for the comics)