You missed the original contoured keyboard, Maltron: http://www.maltron.com/store/p20/Maltron_L90_dual_hand_fully_ergonomic_%283D%29_keyboard_-_US_English.html
I have/had a Dactyl, Advantage2, and Advantage360, but the Glove80 is definitely my favorite!
Bastard keyboards is selling some of the coolest contoured keyboards out there. Furthermore, Quentin who runs the business seems like a great bloke. On top of that, every keyboard is open sourced as far as I know. Cyboard does also make contoured keyboards tailored to your own hands. I’ve heard great things about him as well.
If you’re interested in something different, one really promising keyboard project just launched: Svalboard. It’s a customizable and in many ways modernized version of the Datahand (and therefore not a curved keyboard, but it still retains all of the benefits of a curved keyboard). I just can’t stop to think about that one. It is however way out of my budget.
Ergonomic, split and other weird keyboards
Posts must be of/about keyboards that have a clear delineation between the left and right halves of the keyboard, column stagger, or both. This includes one-handed (one half doesn't exist, what clearer delineation is that!?)
i.e. no regular non-split¹ row-stagger and no non-split¹ ortholinear²
¹ split meaning a separation of the halves, whether fixed in place or entirely separate, both are fine.
² ortholinear meaning keys layed out in a grid
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