Ergonomic keyboards...
I've been using these since the very first 5 pin full-size DIN Microsoft Natural, and my RSI has not come back.
The pain point remains the haptic feedback - after being forced by colleagues in the open plan to abandon my last iteration of the MS Natural, I've been working with the sculpt and - since its demise - a Logitec K860. Haptically not bad, but I miss the key-bashing joy of a proper keyboard.