It's not strictly keyboard-only, but several music notation programs (eg., Finale) have a keyboard (QWERTY) interface for quickly entering music. They have a M

It's not strictly keyboard-only, but several music notation programs (eg., Finale) have a keyboard (QWERTY) interface for quickly entering music. They have a MIDI keyboard interface, too, but that's obviously not what you are asking. :) I would say that the advantage of a keyboard (non-mouse) interface is that you don't have to "aim" in order to move to the next component, you just press "enter", "tab", or an arrow key. Having said that, many spreadsheet programs could be considered to support a keyboard interface, as well as your favorite calculator app. EDIT: Adding that many command line tools fit this. Of course there are text editors like Vim, but also tools like htop.