CS-Cart Multi-Vendor - On-premises eCommerce marketplace builder
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.
SmartEngage - Cross-channel autoresponder for marketing automation
Gumroad - An all-in-one solution to sell your work and grow your audience.
GreenRope - GreenRope is a powerful all-in-one CRM platform designed for small and medium-sized businesses.
WooCommerce - A freely available eCommerce plugin that enables shop facilities on your WordPress website. Functionality enabling extensions & beautiful themes available.