One of my co-workers pointed out that stored energy in a Li-Io battery can often be released in an extremely rapid manner by shorting the leads...
So how about this: put the battery at the bottom of a rocket shaped device, as soon as the device is attached to the rail, short the leads. When the battery explodes, the minibot/rocket will be propelled to the top....
It would take a lot of batteries....
And probably violate safety rules.....
But, it would meet the new clarification of <G19>....
