Spur gears, chains and sprockets, timing belts - whatever method you prefer. Youre most likely to have seen drive systems gearing down the speed of the motors at the events youve been to.

Off-hand examples:
Chains and sprockets - DB5
Spur gears - Batterbot
Timing belts and pulleys - Pillow Torque, Pain in the Asp.

Theyre all effective methods of gearing the motor so that the drive has enough torque to power your featherweight. Obviously the speed and amount of power your featherweight can produce depends on the ratios used with the gears, sprockets, pulleys etc