Steal somebody's personal car, then drive to gas station to change plates, then you will get locked in a black screen for 10-20 seconds then be trapped in an animation permanently until you relog.
This was due to the vehicle being destroyed upon being respawned. This has now been fixed (the vehicle won't be destroyed), but also I've made it so you can't change the plates on someone else's vehicles. When custom plates are added it would be annoying if some random guy can go change your plates..