Sleepytime : Sleep Scheduler

Sleepyti.me works by counting backwards in sleep cycles. It uses sleep cycles of 90 minutes to calculate the best time to wake up. Waking up in the middle of a sleep cycle leaves you feeling tired and groggy, but waking up in between cycles wakes you up feeling refreshed and alert !
Give it a shot, sometime, though... you might be pleasantly surprised at the results !
Inspired by sleepyti.me (by David Shaw).