actually, think of the possibility if we are to even use half, or even 40% of our brain.

either our bodies would not be able to keep up with the vast amount of electro-stimuli through the body, and we'd dissolve, rip apart, or implode into big balls of energy...

or we'd be capable of large-scale brain activity, such as telekenisis, mind-control/reading, maybe even the manipulation of time and space itself.