Here are my chording keyboard references: Start with Wiki: https://en.wikipedia.org/wiki/Chorded_keyboard Douglas Engelbart's chording keyboard looked like piano keys: https://en.wikipedia.org/wiki/The_Mother_of_All_Demos https://www.youtube.com/watch?v=yJDv-zdhzMY "The Mother of All Demos is a name given retrospectively to Douglas Engelbart's December 9, 1968, demonstration of experimental computer technologies that are now commonplace. The live demonstration featured the introduction of the computer mouse, video conferencing, teleconferencing, hypertext, word processing, hypermedia, object addressing and dynamic file linking, bootstrapping, and a collaborative real-time editor." Here's a product with a chording keyboard: https://en.m.wikipedia.org/wiki/Microwriter The Microwriter is a hand-held portable word-processor with a chording keyboard. First demonstrated in 1978, it was invented by UK-based, US-born film director Cy Endfield ... Take a chording keyboard and wrap it around a stick or put it on a small hand-held remote and you have a keyer https://en.wikipedia.org/wiki/Keyer or a "Twiddler", intended for wearable computers: https://twiddler.tekgear.com/ The Twiddler has been "reinvented" as a cordless motion sensor wearable https://www.tapwithus.com/ as discussed here: https://news.ycombinator.com/item?id=17557593 Everything old is new again! -- jeff jonas