An interesting phenomenon about stationary type speed bumps that might come in handy for someone someday: If you drive over them at high speed, you hardly feel them. It takes some guts to do it the first time, but the inertia of the vehicle keeps it from bouncing like it does at low speed. It makes quite a thump and I would recommend you do it with somebody else's car not your own, but it really works. Something good to know if you ever find yourself behind the wheel of a getaway car.