Raymond Li has designed a "jetpack" that uses water to push the rider into the sky instead of burning rocket fuel. It will certainly let you fly, but don't expect to be taking water jetpacks to work any time soon.
Li's Jetlev-Flyer uses twin water pumps to thrust the rider into the air. And the high-velocity water streams do, in fact, give the rider an altitude of up to 30 feet, and they can steer the device by pushing on the handlebars to properly angle the stream.
However, the use of the Jetlev-Flyer is extremely limited. Because an enormous mass of water is required to achieve the necessary level of thrust for any amount of time, the water cannot be carried on the jetpack itself. Instead, a small vessel is dragged behind the jetpack, pumping water into a long hose attached to the back of the pack. Thus, the Jetlev-Flyer only works near a body of water and is essentially a Jetski, albeit a rather epic one.
Li plans to put the Jetlev-Flyer on sale later this year. So, if you have about 130 grand to burn, you too can have your very own pseudo-jetpack.