Maybe you think im joking, but im not.
Anyone who has a little knowledge on the global hobby of water rocket building knows even a 1.5 liter pepsi PET Bottle can handle up to 50 bar of pressure and can reach hights of over 100 meters for less than 20 $ building investments. Professional hot water rockets are currently being devolped by Aquarius Aerospace
http://www.aquarius-aerospace.de/index-e.html
in Germany with the goal to serve as starter boosters of conventional rockets and as a start assist of the projected European RLV Hopper Space Shuttle:
http://www.dw-world.de/dw/article/0,,1196314,00.html
Now taken the enviormental friendliness of water, the high amount of control and safety of non explosive fuels, the incredible low cost, i think it would just be obvious to start research on personal water powered jetpacks.
The folowing Nihonjin who is undoubtfully anything but too small to be a stormtrooper proves the concept for a couple of bucks. Maybe he doesn’t realize how profound the game is he is playing:
Link: sevenload.com