>An item where you could dump electricity into it once, cut power, and have it resist gravity -- forever, and for free! -- is absolute horse shit. Um, you are

>An item where you could dump electricity into it once, cut power, and have it resist gravity -- forever, and for free! -- is absolute horse shit. Um, you are completely wrong. There is a difference between force and energy. It is certainly possible to expend a small amount of energy to create a force which lasts in perpetuity. Energy = Force x Distance, and if there is no displacement in distance, then no energy is spent by the exertion of a force. Not to say that making hoverboards and flying cars is an easy engineering proposition, but that is due to the parameters of the problem, not due to any intrinsic issue with the physics of providing a force against gravity. If people weighed a nanogram, or the Earth's magnetic field were 1 Tesla, or the electrostatic potential between the stratosphere and the Earth was 100,000 times stronger... any one of these and we'd have had hoverboards a long time ago. But that's just numbers. There is no problem with spending a finite amount of energy to create a perpetual force.