Array of squares telling the time. Outer 12 squares indicates the hour of the day. Inner squares indicates the minutes: large 3 are the tens, small 5 are the ones. Seconds are indicated on the top and bottom. 
Color customized. Same color for each section uses hollow/filled squares.

24-hour digital clock made from 100 squares.

Left half indicates hour; right half, minutes. Ticks up for the first half, ticks down for the bottom half. Color configurable.