The easiest way to explain how ThinkGeek's new watch works is like the planets tracing a path around the sun.

The three concentric circles rotate clockwise with each gap in the circle communicating the precise time.

The hour, minute and seconds are defined by the outer, middle and inner rings respectively.

We think should mean the time on the face of the watch shown is about ten past six but do hit the comments if we've got that wrong...

On sale now for $90 - it's a little different from the plethora of binary offerings out there.