Ecwid is a free shopping cart. It can be added to websites and embedded on social media networks. It's easy to use and efficient.
It currently accepts many different traditional payment methods. But there is currently a request for Bitcoin to be added.
I cast my vote, and there's currently 639 votes for it. This would be an amazing way to introduce quite a large group of people to Bitcoin, and it would make it easy for small-businesses, indie musicians, and artists to join in the Bitcoin economy.
http://ideas.ecwid.com/forums/22031-customer-suggestions-ideas-for-ecwid/suggestions/1975985-add-bitcoin-as-a-payment-method