The Voyager keyboard
This is going to be the slowest entry I have ever typed on here. Yesterday I took delivery of a Voyager keyboard, which is an insane piece of kit, and am now embarking on the very steep curve of learning to type on it.
The keyboard comes with a comprehensive set of bits and pieces; cables of multiple lengths, a large selection set of spare/alternative keycaps etc, and the online set-up process of the keyboard is really simple and well-handled. All modifications are flashed to the keyboard's built-in firmware, so all changes are carried over no matter what machine you then plug the thing into.
The desktop footprint of this keyboard is tiny, in comparison to every other keyboard I have tried.
BUT it has taken ten minutes to type this so far, so there's that...
My experience with similar devices is that you only make progress if you really commit to full-time use, so you have to accept that you're going to be typing slowly for a while. I'll let you know how I get on...
Here's a more comprehensive overview: