Free yourself from proprietary to-do systems. todotxt.net is my preferred todo.txt client for Windows. I love knowing that there is no company that can discontinue, make the service more expensive, etc. It's a very logical program.
Try QTodoTXT its fork based on todo.txt but with another GUI.I used it for a very long time and did really crazy things with the tool in my time management.
As far as I can tell, this is the only todo-list-type program that you can use from the command line.
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