It looks nice.

Only problem is that it though it only changes one time per second, the requestAnimationFrame() mechanism will cause the clock to wastefully repaint itself many times per second.

Actually instead of fixing that, maybe it would be possible to interpolate sub-second-precision positions, to have a smoothly moving second hand.

Or, here is an idea: simulate the impulse function of each pop of the second hand: how the hand overshoots, followed by the decaying oscillation known as "ringing".