Kajabi - Kajabi is the only Knowledge Commerce platform today with everything you need to market, sell, and deliver your knowledge online.
Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!
Tendenci - Tendenci - The Open Source AMS is a cloud-based all-in-one management SaaS solution for Non-profits and Associations.
Mailbird - Mailbird is the best email client for Windows 7, 8 and 10
YourMembership - YourMembership provides membership management software integrated with social networking features.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.