After sleeping I've noticed there is a rested effect on me, but apart from keeping me from sleeping again, I don't see any other effect.
3
Sleeping advances time. Other than that, it has no effect.
The developer answered a similar question on the Steam forums here. The buzz just prevents you from sleeping again immediately.
Its just a mechanism to prevent players from exploiting the time advance to trivialize the timers on some of the house upgrades
