10: Portable Vehicle Traffic Speed Bump
Tired of those pesky teens speeding through your neighborhood? No speed bumps on the ground to keep them in line? Well, there is also an option for that, and it is the Portable Vehicle Traffic Speed Bump. This unique device can be placed anywhere, and you can have a portable speed bump setup within minutes (via The Sun).
The idea is novel at best, as the portable speed bump probably wouldn’t stop anyone from speeding. But if you have an event where little kids will be present, and want to slow down the flow of traffic, then this might work.