Via Jeff's Arduino Blog, the Princess and the Pea Alarm Clock:
"No ordinary alarm clock: the Princess and the Pea Alarm Clock ('PPAC') leaves no room for snoozing, inflating a green 'pea' between the mattress and box spring, making it impossible to stay in bed. In the tin can, a homemade Arduino-compatible board with clock and memory chips handles the alarm clock functions, and a power block under the night stand provides power and relays driving the sprinkler valve or other alarming alarm functions."
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