An optical mouse uses a beam of light and an optical sensor to detect movement over a surface -- there are no moving parts.

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When sound waves enter the tube, the vibration of the droplets will cause the sensor to detect changes optically as the beam is disturbed, supposedly resulting in near-perfect vocal reproduction.

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Since there's no physical interface on the device to configure WiFi, the company's developed Blinkup, a way to enter SSID and password information on any iOS and Android smartphone and beam it to the Electric Imp's light sensor by rapidly pulsing the handset's screen on and off.

ENGADGET: Hands-on with the Electric Imp at Maker Faire (video)