Hydrogen peroxide powered rocket packs fly for around 30 seconds, because they have a specific impulse of around 125, meaning that one pound of propellant can make 125 pound-seconds of thrust, meaning that it takes about two pounds of propellant for every second you are in the air. Mass ratios are low for anything strapped to a human, so the exponential nature of the rocket equation can be safely ignored.

A pretty hot (both literally and figuratively) bipropellant rocket could manage about twice the specific impulse, and you could carry somewhat heavier tanks, but two minutes of flight on a rocket pack is probably about the upper limit with conventional propellants.

However, an actual jet pack that used atmospheric oxygen could have an Isp ten times higher, allowing theoretical flights of fifteen minutes or so. Here, it really is a matter of technical development, since jet engines have thrust to weight ratios too low to make it practical. There is movement on this technical front, but it will still take a while.

John Carmack

Well, you are entitled to your own opinion. Maybe you should have tried a different type of medication before you chalked the whole thing up to a doctor's inferiority complex. I was always extremely strong in math and science classes (when I actually bothered to do the homework), but struggled in anything else that didn't captivate me the way math or computers did. I wasn't "officially" diagnosed until I was in college, and this was after just sliding by with a 2.7 GPA for three years. I always suffered from the "inattentive" symptoms rather than the "hyperactive" ones. I got a prescription for Ritalin, and I found that it didn't help me study one bit. In fact I was bouncing off the walls, driving my wife crazy, generally acting like a 6-year-old on Jolt Cola. Two weeks later I tried Adderall, and the difference was quite real. I found it to be less of a "mind supressor", and more of a focusing aid. Instead of having spurious thoughts that would drag me off to distraction whenever I needed to concentrate (i.e. homework-time), I could now reign in my rambling thoughts and focus on the task at hand, even if it seemed tedious at the time. In a matter of weeks, I found myself finishing homework during class, getting tedious work out of the way quickly to give myself more spare time in the evening. I stopped forgetting about assignments, tests, meetings, not locking my keys in the car, etc, and could finally perform up to my full potential in *all* my classes, not just the ones I didn't get bored with after 5 minutes. During the last year of college, I got straight A's (only a single A-minus) in courses that were as hard, if not harder, than the ones I had been failing, retaking, and marginally performing. It's my opinion that this disorder is real, and not some excuse for laziness, underperformance, or any other chalked-up scheme by doctors or parents. You really should consider Adderall, or some other treatment before you write off the whole thing. Good luck.