I would mention Total commander and Quick Access Popup as two well known ones, but two gems that I see are undiscovered are:

- TouchCursor https://martin-stone.github.io/touchcursor/ the only one I found that allows you to use Space as modifier key, and works flawlesly (with other ahk scripts handling hotkeys running simultaneously). Praying it does not stop working with some Win10 update, as it is not being worked one, it seems

- https://github.com/zsims/hunt-and-peck for more mouse free operation of any program.