my printer is alive

I didn't remember having my power supply to the printer switched on that night. Somehow in the middle of the night I was awoken by the printer. It was doing the familiar 'clean up' which you would get everytime you flicked the switch at the power supply. Feeling sleepy and puzzled I got up and shut the damn thing down and then went back to sleep.

Crap. It's really scary. It's as if someone flicked the power on when I was in bed. Even if the switch had been on before, why would it just start 'cleaning' itself if it had been lying on standby.