In the last 6 months I've notice that the turn signals (blinkers) on my 2001 Pontiac Grand Am stop working, (no turn signal on dashboard or in the actual lights) but as mysteriously as they stopped they will start working again.
I thought perhaps making a left or right turn sharp enough to turn the blinker off (assuming it was working as normal) was a key to resetting it, but I disproved that theory tonight on the way home.