While it's been possible for ages to record keyboard and mouse commands as macros, quality assurance teams sometimes can't have any tracking software running -- a real pain when trying to recreate a bug in an online RPG or other input-heavy apps.

ENGADGET: Insert Coin: Emukey EK1 runs mouse, keyboard macros purely from hardware (video)

The sensor, or an array of them, would record the movement of your hands while they type against a keyboard projected by laser on your desk, or even in the space in front of you.

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