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

Todo.ly - Todo.ly is an intuitive and easy to use online Todo list, and Task Manager. It helps you to get organized, simplify your life, and to get things done. Create todo lists, and manage them online from anywhere.

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

Planisware Orchestra - Planisware Orchestra is a best-in-class project portfolio management software and solution, providing an agile approach to bring all the stakeholders on the same page.

EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.

The Hit List - Your life is complicated, but managing it doesnt need to be.