Shopify - Shopify is a powerful ecommerce platform that includes everything you need to create an online store and sell online. Try it free for 14 days.
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
WooCommerce - A freely available eCommerce plugin that enables shop facilities on your WordPress website. Functionality enabling extensions & beautiful themes available.
Textpattern - Textpattern is an elegant content management system that is free, open source software.
BigCommerce - BigCommerce provides ecommerce software solutions and shopping cart software for online businesses. Try it free and start selling your products online today!
TYPO3 - TYPO3.com - Infos, SLAs, Extended Support Versions and more