Shoppy - Automatically get order notifications & summaries in Slack
Sell.app - Sell.app is the easiest way to sell digital products online. Spin up your own storefront in just a few minutes and start selling instantly.
AutoBuy - AutoBuy is an all-in-one payment processing and e-commerce solution.
Selly - Selly is a complete selling system.
WooCommerce - A freely available eCommerce plugin that enables shop facilities on your WordPress website. Functionality enabling extensions & beautiful themes available.
Lemon Squeezy - Sell digital products the easy-peasy way