Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
Binery.co - BINERY powers the financial back office for startups and small businesses. We provide a real-time and seamless bookkeeping experience for growing businesses in Asia and beyond!
Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.
Remember The Milk - Remember The Milk is a task and time management application for mobile devices.