Last Clock

Last is a clock that is a record of its own history. Like a familiar analogue clock, it has a second hand, a minute hand and an hour hand. The hands are arranged in concentric circles, the outermost circle being seconds, the middle circle is minutes, and the innermost circle hours. Each of the hands of Last are made from a slice of live video feed. As the hands rotate around the face of the clock they leave a trace of what has been happening in front of the camera. Once Last has been running for 12 hours, you end up with an easy-to read mandala of archived time.
http://lastclock.net/