Gumroad - An all-in-one solution to sell your work and grow your audience.
Swell.is - Customizable, API-first ecommerce platform for innovative brands, startups, and agencies.
Payhip - Sell digital downloads, courses, coaching, and more from one simple platform.
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.
robora - Robora is a service which aims to help you sell anything, anyway you like.
Vendure - Open-source headless e-commerce framework for developers