PracticePanther - PracticePanther offers CRM, invoicing, time tracking and communication solutions for law firms.
iDempiere - iDempiere Business Suite ERP/CRM/SCM done the community way.
Sticky.io - Sticky.io is one of the leading online subscription and recurring billing platforms that help streamline subscription commerce by enabling you to run the subscription business based on your goals.
Zoho Subscriptions - Smarter recurring billing and subscription management software
PHC FX - PHC FX is a comprehensive solution that offers a wide range of functionality at any price.
Subscription Genius - Subscriber & mail list management for publishers