No keyboards, but -- Astrid Lindgren, the legendary Swedish children's writer, wrote her manuscripts using the Melin shorthand system. One can browse a bunch of her notebooks online, side by side with a Swedish transcription [1, 2].
Quoting one of the linked sources: "These manuscripts have long been seen as the key to new advances in research on Astrid Lindgren. The explanation for why no one has taken on the task is that Lindgren wrote in shorthand, given the well-established view that her stenography was almost impossible to decode. When we started examining the material to see whether using digital methods to interpret it was feasible, we saw that manual reading, too, was relatively simple if you know shorthand."
I got curious and found a comprehensive paper about using computational tools (handwriting and image analysis) to transcribe Lindgren's manuscripts [2]. Interesting stuff.
Oh, and I think Astrid Lindgren actually also worked as a shorthand typist during a period in her life.
