ChordedKeyboard''''''s represent letters (and maybe words?) with the simultaneous pressing of several buttons, rather than having each button represent only one symbol.

See...
* http://en.wikipedia.org/wiki/Chord_keyset
* http://www.tifaq.com/keyboards/chording-keyboards.html

Includes stenotype machines, used in many court rooms, with typical speeds up to 300 words per minute, though these represent sounds and don't represent spelling.
http://en.wikipedia.org/wiki/Stenotype_machine

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CategoryKeyboard