to be fair the kid that did it is a mate of some guy i work withs son, he was pretty shitted up and he didnt realise what was gonna happen, the girls were the ones who suggested it and they were having a laugh. and no, none of them were hurt. seriously
I once did this with a roundabout near me and a Go-Ped rear wheel. I had to lay the goped on its side on the floor, and put the rear wheel against the rubber bump strip around the edge of the roundabout. It picked up some serious speed. A mate of mine flew off it when it was spinning up too! But 5 years ago we didnt really have video phones or anything. So I didnt get a clip of it.