Backflip - Selling your electronics just got easy
Square Online Store - Build your own online store with Square
Pattern by Etsy - Turn your Etsy shop into your own website
Swell.is - Customizable, API-first ecommerce platform for innovative brands, startups, and agencies.
Sharetribe - Build your online marketplace business. You don't need a developer.
WooCommerce - A freely available eCommerce plugin that enables shop facilities on your WordPress website. Functionality enabling extensions & beautiful themes available.