The Finite Improbability Drive is a kinetic folly designed for a wedding. The colour changing LEDs and plywood gearbox are designed to generate movements to mimic those of bioluminescent jellyfish. The ‘ribs’ move both vertically up-down and also rotationally to-and-fro. As a result of a gearing based entirely on prime numbers, the gearing generates a unique set of movements which repeats only after 3,063,028,111 turns of the crank handle to represent the chance encounter of two humans on planet earth.