Most readers will know that we have a "light" e-commerce solutions but we have now introduced a much more powerful solution which is based on an open source solution for maximum flexibility. You can see an example at www.thebiginternetshop.com/bigshop - let me know if you'd like a username and password to play with the administration system.
nopCommerce has hundreds of features and is very customisable - we'll be using it ourselves and linking it our new CRM and accounts systems in the very near future. If you would like an example of your own to play around with please just let me know and I'll set one up on your domain.