Todomoo calls itself a todo manager. It is primarily aimed at keeping track of schedules for paid projects but it can be used as a simple to do list as well.
Todomoo’s interface is a tab like presentation with each category having its own tab. Tasks belonging to each or all categories can be viewed by clicking on their respective tabs. Tasks are added via the New Task button (or from the program menu: Task —> New Task) and assigned a category, name, description, color and priority. Additionally the new task window offers options to add creation, due and completed dates plus a timer to keep track of time spent on the task. Keeping track of payments is made easy by assigning per hour rates and a due date. Multiple notes can also be added to tasks with the tabbed interface indicating how many notes exists for any particular one.
Todomoo also supports sub tasks. These are made somewhat more useful because sub tasks can keep their own timers and payment details separate from the main or parent task. Those details can then be added and included when a parent task is complete.
Tasks can be exported to a *.csv (comma separated value) file. Todomoo can keep backups of its SQLite database. It is available in both installer and portable versions.