Bald Eagle Persuader Boat
There is a boat that looks oddly like the Gungan submarine in Star Wars Episode 1. It is called the Bald Eagle Persuader. It travels ridiculously fast on water. If you drive it in a straight line for long enough it takes off and wings grow from the side. When you land it, wheels pop out underneath. It is very difficult to control. It appears about one in every ten visits to the mansion near a safehouse. it cycles in this order: sea, air, land. If you go from the air to the sea it will just explode.