Pendumum clocks made in Phun :-)
Phun, the 2D physics sandbox: http://www.phun.at/
The gear is made with Phun Gear Creator http://codebot.org/articles/?doc=9516
Beware of the regional settings wich may screw up decimal point in the .phn-files from the gear creator. Very frustrating until I saw the solution at the Phun forums (thanks!). In short, make it a dot(punctuation . ), not a comma!
Sorry again for the flickers.