The Horological Machine N°4 Thunderbolt (or HM4 Thunderbolt for short) insists that it's quite a special watch, inspired by aviation. Check out the marketing prose:
The aviation-inspired case and engine of the Thunderbolt are one. Neither would, nor could, exist without the other, yet each is so transcendental as to be able to stand alone as a work of art in its own right.
Practicality not withstanding, the watch is unique in a number of ways. Both of its faces—which indicate the time and "power reserve" (how much energy is left in the spring)—are oriented sideways, facing down one end of the leather strap.
Opposite the faces are two crowns, one which sets the time, and the other to wind the watch. The titanium and sapphire case features multiple transparent panels, to show off the watch's mechanism. The results is a watch that looks like a mini-cockpit. Unfortunately, the face of the barrel that displays the actual time is small and difficult to read.
The price to own one of these? $158,000.