Hye-Yeon Park has devised a clock that visualises time as numbers melting into one another which I like a lot.
On the subject of time, Christian Marclay's film piece The Clock currently on show as part of the British Art Show 7 at the Hayward is excellent. It "features thousands of found film fragments of clocks, watches, and characters reacting to a particular time of day. These are edited together to create a 24 hour-long, single-channel video that is synchronised with local time. As each new clip appears a new narrative is suggested, only to be swiftly overtaken by another. Watching, we inhabit two worlds; that of fiction and that of fact, as real-time seconds fly inexorably by."
Mesmerising stuff although 24hours solid watching is a heavy commitment.