@doboprobodyne one tiny problem with the "type equations at the speed of thought" -- most #mathematicians can *already* type equations and such at the speed of thought, because TeX notation is so deeply ingrained in their brains/fingers. For example, if I'm thinking of
\[ \int_0^{2\pi} \sin^2(x)\, dx \]
then I just automatically type
\int_0^{2\pi} \sin^2(x)\,mathrm{d}x
without really thinking about it, and I don't have to take my hands off my keyboard.
That said, it looks like a fun little device, especially if it's QMK compatible.