Over the last few days I finally found the time to set up an online shop for my company, to resell CodeGear software in Italy. The online shop is at http://shop.wintech-italia.com (the pages are in Italian, but you should be able to see the visual effects regardless of understanding the details)
If the first page of the shop looks like... any other online shop, the detail pages (like this one for Delphi 2007) have a different approach. Rather than listing the various product versions with their prices in a table, a user can select a number of options (with classic radio buttons) and the price for his selection will be displayed, along with shipping costs and taxes. The JavaScript code updates also the PayPal "buy button". I really like it, maybe I should have filed for a patent!
To create this user interface, I set up a simple REST server, that processes an internal JavaScript request returning the price for any given configuration (mostly using XSLT). The browser-based code is all based on jQuery, the superb JavaScript library started by John Resig. The same library is used for the "modal-dialog" effect as you select some of the internal links (like the description of ESD/DVD or of the Supscription).
I'm getting more and more convinced that you can really do wonders with a good JavaScript library, and a little bit of back-end code. I should be able to demonstrate what I mean at one of my talks at CodeRage II. Stay tuned.