Hi Olu,
There are a good few I'm aware of.
www.clarionshop.com is probably the biggest we've done.
We've also added integration for external sites into ClarionShop (allowing the ClarionShop checkout page to look like the site it's coming from.)
The clearest example of this is
www.cstimeclock.com - which is also a NetTalk site. The shopping cart technology we've created for cstimeclock.com is also something we'll be making available in the near future as a "shell example". ie it won't be a free example but it won't be too expensive.
Cheers
Bruce