GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

Mailshake - Mailshake lets you build your professional network through a smart and intuitive approach to cold emailing.

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.

MailChimp - MailChimp is the best way to design, send, and share email newsletters.

Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.