If you're playing co-op, and you put 2 seats on a rover the passenger can take off their own seat and drag it around wherever they want causing them to fly around at super high speeds for as long as you want. But afterwards you cannot get out of your seat, so you have to kill yourself (leave) to get off of it. So DO NOT do this if you're the host of the world. You will not be able to get out of your seat, ever.