Rather than simply riding the cable under the the influence of physics, it features an RF remote with speed control and the ability to run in reverse.

ENGADGET

Next week, before MPs disappear from Westminster for the Christmas break, announcements on high speed rail and perhaps details of the government's reverse on school sports funding will follow.

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Its two high-speed electric motors operate as one but can act independently (and incidentally, by using reverse torque instead of friction for braking, the motors convert the energy of your motion to help replenish the battery).

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