Has anyone else had the Alarm go off for no reason. Even when the car is unlocked and no one around it?

Mine has done it twice now in less than 24 hours. Last night the car was tucked, safe and sound, in the garage (unlocked and garage door closed) and as the wife and I were watching the news the alarm started screaming in the garage. I went out stuck the key in the ignition and turned it on to kill the alarm. Then just a few minutes ago.... The car is sitting in my parking space, right outside my office, and it went off again. No one around and the car was unlocked. It's really strange!!! :? :roll: