These videos were designed in After Effects to simulate my conceptualization of a "light clock."  It is devised with three lights (originally red, green, and blue) aimed at a the back of a translucent surface with a small pillar in the middle.  The three colors blend into a pure white, but where the pillar creates a shadow, the respective light's complementary color appears.  Each light (not shown) is attached to a ring that rotates around the center and each ring is further away from the clock surface.  The further the ring, the more acute the angle to the pillar, and the shorter the shadow, creating the second, minute, and hour hands, respectively.  

Beyond the simple concept.  The clock's back, with the rings, can be made of clear plastic (with the optional cover) allowing the three lights to pour into the room and, particularly at night, create multi colored shadows (it also lets people see how it works).  Furthermore, the lights needn't be RGB.  Any three colors in respectively triangular postions around the color wheel can result in a net white with complementary shadows.  This allows the clock to be programmable with an infinte number of color combinations or color-changing schemes.  The clock can change from color to color in any fashion.  It can be configured for the net color to be something other than white (though not ideal for seeing the hands).  Or each hand can transition through the entire spectrum over the course of a minute, an hour, or a day (see below)

It can also have a "green," power-saving color setting.  The clock is twice as bright when the three lights are Cyan, Magenta, and Yellow (hands are Red, Green, and Blue) than when the lights are RGB (hand CMY).  The clock could transition from one configuration to another depending on room brightness.  The settings of the clock could be controlled by remote or by another more advanced home asthetics system like the Phillips Hue.  And, it's really quite fascinating to observe the simple, beautiful nature of light and color.