osCMax

From the official osCMax website:

osCMax v2.0 is a powerful e-commerce/shopping cart web application. There are many advantages to using osCMax as your e-commerce/shopping cart for your web site. It has all the features needed to run a successful internet store and can be customized to whatever configuration you need.

You can visit the official osCMax here: http://www.oscmax.com/

Wallanet has set up a demo version of osCMax so you can try it out. We've included access to the admin interface as well.

The demo version can be found here: http://demo.wallanet.com/oscmax

You can login to the admin panel for this package by going here:
http://demo.wallanet.com/oscmax/admin
Username (email): webmaster@wallanet.com
Password: testdemo

To learn more about this e-commerce solution and all the other e-commerce solutions that Wallanet offers go here: http://www.wallanet.com/open_source_packages/e_commerce