When the independent Swiss watch brand HYT was launched in 2012 it revolutionised the industry straight away with some pioneering fluiddynamics-based haute horlogerie that unites two immiscible fluids – one clear, one coloured – in tiny capillaries. To see the time, you look for the boundary line between the fluids for the hours, while the minutes are read off a separate, conventional dial. Their newest model, the H4 Metropolis, goes even further by adding some mechanically operated lighting to the mix. As you’ll probably notice, this 94,000 USD titanium watch has two crowns. The upper one at two o’clock is for winding and setting the time. The other, at four o’clock, is used to charge a secondary mainspring, which is used to power a small generator connected to two blue LEDS. If you push the crown in and then let go, you’ll be given a three-second battery-less light show that’ll leave you in absolute awe. HYT’S H4 Metropolis is limited to 100 pieces.