The fine folks over at Hodinkee have really outdone themselves with this one. The Portuguese Sidérale Scafusia is one of the most complex timepieces IWC has ever made, and the ten years it took to develop this wondrous beauty proves just that. The Scafusia features solar time, the sidereal time (both can be set independently), power reserve and a very large tourbillon as seconds display. The rear side displays Customized celestial chart and horizon, sunrise and sunset display, sidereal time and solar time, day, night and dusk display under celestial chart, perpetual calendar with display showing leap years and number of day.
The details are immense on the Sidérale Scafusia so be sure head on over to Hodinkee for more information on this modern-day classic.