Also, the AC fan...

Also, every once in a while, my AC fan just turns off for no reason: the air stops blowing out of the vents, and the light indicator on the AC button in the dash turns off. Sometimes changing the fan speed selector switch causes it to turn back on, sometimes pushing the AC button on and off real quick turns it back on, sometimes it just comes back on when it wants to. The air is blowing nice and cold when it does blow, and it usually only stays off for less than a minute...any idea what could cause this?