This is a true binary clock, far geekier than those things that show the hour and the minutes as separate binary numbers. This one shows the number of minutes since 12:00 (noon or midnight) as single binary number. The low 5 bits are in the inner ring; the high 5 bits are in the outer ring. In each ring, the lowest significant bit is at the upper right, and significance increases clockwise. So, in the image above, the time is 5:41.
(It is possible to configure the clock to show the time in text as well.)
The colors used to indicate 0 and 1 are configurable; there are a couple of flat color choices, a few based on gems, and simple black-and-white to accommodate colorblindness.