If a lack of a face is a defining characteristic in minimalist watch design, the Elusive watch concept is the most minimalist watch ever created. The Elusive watch was designed by David Blanc, an intern at Dassault Sytemes.
The Elusive watch concept is completely faceless -- no hands or numbers to be found. Instead, the watch is designed to project the time and date on your skin with a laser. The time is hidden unless you press the button, saving you battery life and leaving people to wonder as to what purpose the colorful bracelet on your wrist serves.
Minimalism has slowly but surely infiltrated nearly all aspects of watch design. I wouldn't be shocked to see faceless watches like the Elusive watch become the standard sooner rather than later.