Franck Muller Aeternitas Watch
One look at the Franck Muller Aeternitas and you can tell it has a lot going on. This watch is for those who really get into complex mechanical complications. Instead of a regular perpetual calendar this watch is designed to follow a 1,000 year cycle without correction and takes into account the rule governing the Gregorian calendar. An article in Europastar breaks down the details. The watch comes in four version and uses a Cintrée Curvex curved automatic movement. The traditional perpetual calendar has the day, date, month and moon phases taking in to account the variations in each month. It also takes into account leap years but hast to be adjusted three times in a row every 100 years because in the Gregorian calendar every 400 years, the leap year is canceled for three centuries in a row and is re-established on the fourth century. The Aeternitas eternal calendar is a module on the watch which takes this into account. It has two sets of wheels, the first is a set of a wheel of 10 years, a wheel of 100 years and a wheel of 1,000 years; the second set is designed for the setting. The watch also has the retrograde date at 12 o'clock, days, months, 24h day and night, normal leap year cycle and indicates the time equation. The equation of time is coupled with the calendar, which means that even when the watch is not wound for many years, at the moment of its correction, the equation of time follows the calendar.
With so many complications to keep track of and that big tourbillon obliterating the six o clock spot, the dial is a bit cluttered. It's a bit of a case of Dance Ten, Looks Three. The watch sells for around one million euros. Pricey yes, but consider it a bet that the world as it is will continue another thousand years (and looking at it that way it works out to only 1,000 euros per year).