The Flyboard, invented by Franky Zapata, is a jetpack system that lets users swim and jump out of the water in a similar way dolphins do.
Franky Zapata is a very famous athlete in French Ski racing (a very fast type of sport with obstacles, kinda like Wave Race for the N64). Maybe through a stroke or genius or just boredom, he came up with the Flyboard.
The way it works is that it has a hose connected to a Jet Ski motor. Those attach to a pair of jet boots with stabilizers. When properly trained, people can jump out of the water over 30 feet in the air!
Check out how awesome the jetpack looks in the video below