This Demonstration is a simulation of a circular mass accelerator based on the principle of the hula hoop .
A mass sliding with very little friction inside a tubular ring can be accelerated to very high speeds. The accelerator ring gyrates eccentrically with a very low amplitude at an ever-increasing angular speed while keeping the mass in phase with its own rotation. When the desired speed is finally reached, the mass is released from the ring and hurled into the atmosphere.
There are projects  that use this principle to launch material supplies into orbit much more economically than by using more conventional rocket spacecrafts.