Place markings in a subway tunnel indicating they are spaced, for example, one meter apart. These can be seen through the windows of a moving train. In actuality the markings are only spaced one decimeter apart. Passengers will think the train in moving ten times faster than it really is.
-- rcarty, Aug 04 2011

The lack of Blue Shift will reveal your strategem.
-- 8th of 7, Aug 04 2011



random, halfbakery