Greubel Forsey Quadruple Tourbillon (2011)

It comprises two pairs of tourbillons, each with one inside the other. Each pair of tourbillons contains 128 components but weighs just 1.17g. The movement took five years to develop, contains 531 parts. The polishing and decorating of the components took 500 hours of work. 18k rose gold case in 43.5mm, priced at US$1,000,000.00