Major manufacturers ship laptops with touch pads that respond to fingertip presses at varying force levels, which is nice confirmation for this earlier research project.

In it, pressing movements that occur after the initial pushdown of keys on a computer keyboard are detected, classified, and used.
It is shown how this can simplify existing user interactions, by seamlessly replacing existing sets of simultaneous key presses with single key presses.

Moreover, a rapidly learnable new class of interaction scenarios is proposed, in which users can navigate interaction options, get full previews of potential outcomes, and then commit to one outcome or abort altogether – all in the course of a single key press/release cycle.