A split ortho homebrew keyboard (helix) that I can program with qmk so that I have shift esc enter space and special keys on other layers right where I want them. Or a dedicated Ctrl-a key for tmux. It virtually eliminated my pain. The OLED screens are useless though and I retrospect I should just have skipped them. I should also have put the two arduinos in it on sockets right away because that USB port will of course break and it’s a pain to desolder it.
A “clearly superior technology” (CST) trackball in the middle of the split keyboard that I try and use most with my left hand to give my right hand a break. It’s chunky, well made, uses standard pool balls as the trackball, and can be easily taken apart for cleaning or servicing. Wasn’t cheap though.