My neighbors' kids got a new swing thing for Christmas. It is sort of like a tire hung horizontally from a tree, except this thing is not a tire but, rather, a webbing inside a rim about the size of a hula-hoop.
They took turns riding it or pushing it. They tried putting their dog on it but it escaped and spent the rest of the day hiding underneath their truck.
The day ended with the six year old going on an especially high and an especially spinning ride. The kid, mid-flight, unleashed a spectacularly awesome vomit spray that managed to drench all of his siblings.