Sundial LED clock
Here is a very interesting concept of indoors sundial clock. A sundial is a device that measures time by the position of the Sun. Since indoors we don't get the Sun to cast a proper shadow for these purposes, it can be replaced with, yes, good old LEDs.
This shadow clock can show all three "hands"; hours just like a real sundial clock, minutes and seconds. Each shadow, or hand, is cast from a different light source - a ring, and each ring is of a different color (RGB). So, there are three rings, each having 12 LEDs (36 LEDs in total) and it is all multiplexed and controlled with AVR microcontroller.
There will probably be a kit of this cool clock soon, so check it out!
© Evil Mad Scientist