One thing I’d like to do sometime, if I get around to it, is making a custom keyboard designed for PCalc, a great iPad calculator app. They have bindings from a standard keyboard to all their functions, but the layout of a standard keyboard isn’t quite what I’d want for it, but a custom keyboard with programmable firmware should make it possible to set up something pretty nice.
I'm sort-of puzzled here. Most desk-calculators use rubber domes with sliders designed to minimize binding on off'axis presses. Cherry MX is not the best for off-axis perssing performance. Why do you want MX over a good RD calculator here?
Ideally a calculator layout would be optimized for touch typing. Most calculator layouts are really quite inefficient because they’re designed for one-finger hunt and peck.
I find desk calculators (including expensive graphing calculators, etc.) to have quite atrocious buttons, which actuate unreliably.