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."

Check a video of the clock in action.