This is pretty much exactly what I use Sublime Text for. On windows I just have to type the windows key, "sub", and enter. Then it pops up with my todo list and

This is pretty much exactly what I use Sublime Text for. On windows I just have to type the windows key, "sub", and enter. Then it pops up with my todo list and various notes. I can open a new tab to jot a thought down. The notes persist despite closing the application and restarting the computer, even without saving to disk.