I love the weird, awkward social situations in the video at the tapwithus website, featuring people interacting with the tap keyboard secretly while they are talking to other people - magnificently strange.

The police will arrest you for wearing brass knuckles if you are caught using this device.

This seems to be capturing finger movements that would otherwise map to a keyboard. I wonder if there is an even more optimal way to capture finger movements and map them to input, if the idea of mapping to keyboard finger movements is discarded.