In the 2007 collection named BLESS No. 32 Frustverderber, German fashion brand Bless added a watch face to a leather belt. This unique hybrid timekeeping accessory comes in either the Casio digital or the analog watch face version. High-end retailer ProjectNo8 has the Casio digital version available for sale in natural or black leather.
Bless models Akari and Ryad show how to wear the analog versions of the watch belts but there is no indication on how they actually read the time strapped around their waist.
Admittedly, when I began researching this, I was hoping that they had incorporated a 1980s Casio calculator watch face to the belt.