I was doing some calculations the other day about whether you could use a magnetic field to repel yourself away from the Earth. It would really help reduce energy cost. However, from what I found, the field you'd be creating would be utterly unmanageable.
You'd need a solenoid about the size of your spine, wrapped almost an inch thick in superconducting nanowire. Then you should put about 10,000 amps through it. But before this, you should set up a slow-mo camera to watch the whole thing contract inwards and crush itself, because that's what'll happen.
You also need to have the solenoid stay perfectly counter-aligned to Earth's field, lest a huge amount of torque wrench it around.
Just a messy solution all around. Sigh. Back to the drawing board.