Silent Alarm Clocks

Expert rating 9.17 Public rating 9.13 Voting is completed

A focused timer-operated water sprayer would be a great silent alarm clock.  The alarm clock would push the button of an electronically operated water sprayer.

The main advantage of this solution is that it's more effective than a sound- or light-based alarm clock that you can switch of and keep sleeping. The water sprayer make the pillow wet and thus unpleasant to sleep on.

Expert rating 7.4 Public rating 7.67 Voting is completed

 A deflated inflatable pillow can be put under the main pillow, beneath the bed sheet. Just before the wake-up time, a timed air-pump would start inflating it, thus making further sleeping uncomfortable.

PS: A similar silent alarm clock can be provided to the passangers by conductors in Japanese railroads.