My father had just gotten a new Italian sports car and was on a trip. He specifically told my brother and I not to even get near it while he was away. And of course we didn't listen to him. We snatched the keys just wanting to start the engine and pretend we were driving. We didn't understand gears and clutches yet so when we turned on the ignition we didn't realize it was in 1st gear. It popped forward right into the wall of the garage and we naturally shit in our pants thinking oh god we're totally fucked now.
Of course we both did the famous brotherly, "He did it" when my dad returned.
