The picture above is a place holder until I can put my Geochron back on the wall and take a picture of it.
According to the Geochron sales brochure:
Geochron is a true global time indicator. Unlike conventional time pieces, which indicate the time at one point only, Geochron indicates the days of the week and the dates of the month that prevail at any given instant, as well as the geographic extent of each. It also shows the sun's zenith position and the distribution of daylight and darkness on the surface of the earth.
Geochron's Mercator projection world map moves slowly from left to right under the protective screen at one inch per hour. It completes the cycle in 24 hours, just as the earth does. It's always high noon along the red longitude line at the center of the map.
Perhaps, the most fascinating feature of Geochron is that it automatically show where on earth it is day and night at the instant the map is viewed. The left edge of the illuminated pattern indicates the moment of sunrise while the right edge indicates the moment of sunset. This sunrise and sunset pattern changes continually as the earth progresses through its seasons. This phenomenon is accurately depicted on Geochron."
Geochron has a web site, describing their product offering.