Yeah ^^ ! That's flyboard.
The guy on the picture is quitte good at it.

How it works: the water propelled by the boat's engine is redirected into the pipe, and the guy has a lever in his hand, allowing him to adjust the engine power and therefore the power of the water jet under his feet.
I did it once (on a pond in France) and it's an unforgettable experience! With the right advices, all beginners can have fun from the first flight.
However, it is relatively expensive... and the carbon balance is not happy.