When Tom took the trash out after dinner, he noticed that the garage door hadn't lowered completely.  When I went out to remedy that and hit the button, the door raised up... but the gear was broken and the chain came loose.  At least it's broken with the door UP, because it can't be moved manually (Tom tried.)  If it had broken with the door down I'd be without a car until we can get someone over to fix it... though I'm less than thrilled to have the garage wide open, especially on a Saturday night.