This german site also uses ubercart. You can rent or buy event electronics.
At the frontpage you see two random images and a select-form for quick access to the main categories.
The frontpage of the shop visualizes the whole taxonomy tree with some nifty javascript-effects.
For the overview of sub-categories and the product-list in a sub-category it uses the "normal" ubercart view.
For every product you get the product description, technical datas and possible product downloads like pdfs, additional images and so on (see the tabs below the description). There's also an own download-site where you can see all available downloads.
After clicking on the black button with the red cross on a product site ("In den Warenkorb legen") you can see a wonderful ajaxified shopping cart 
There is an additional second step in the shopping cart, where you can choose the start- and end-date of the rental products (click on "Nächster Schritt").
The site is only available in german. You can translate it with google or babelfish, but it seems that the design crashes a bit and the shopping cart doesn't work. So I added some screenshots for you.
Greetings from Germany
and big thanks to all Ubercart-Developers and Contributors
Michael
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 | shopping-cart.jpg | 154.96 KB |
(You might add an onblur event to auto-save changed quantities in case someone doesn't hit the save icon. I hope you don't mind me taking some inspiration from it as we redesign on D6.)