YAPML yet another poor man's library that makes things finding it hard to render and taking its time to compile.
In this case the self-replicating polyhedron is intended to give a mechanical touch to your freshly (or not) designed cylindrical surfaces. Hmmmm... you can also thing that those things all-around the cylinder are diamonds and use it for jewelry.
The examples scad provided uses OpenSCAD MakerBot Font Module by grokbeer licensed under BY-SA-NC license (link in the instructions section)
(Just in case you don't read the comments bellow)
Video by sirmakesalot (thank you very much!!)... http://www.youtube.com/watch?v=uz8h--NsX7E
Things using this library :-)
Bowden Clamp for Ultimaker by owen http://www.thingiverse.com/thing:11864
Spindle for 5lb spool by mikeq http://www.thingiverse.com/thing:12871
Knurled "topper" for stepper motors by Pazu http://www.thingiverse.com/thing:13978
Ultimaker Hobbed Bolt Release by bkubicek http://www.thingiverse.com/thing:14505
Hobbed bolt holder by coffeeMaker http://www.thingiverse.com/thing:16136
Shane's Coral Frag Plugs by sgraber http://www.thingiverse.com/thing:16982
Bowden Clamp for Ultimaker (Feeder End) by pit3k http://www.thingiverse.com/thing:17027
Go to http://www.thingiverse.com/thing:6844, grab the Font Module, follow that thing's own instructions to be able to use it and come back.
Go to http://www.thingiverse.com/thing:8796 to get the screw library, follow that thing's own instructions to be able to use it and come back.
Download 'knurledFinishLib.scad' and drop it into your OpenSCAD library folder or the folder where you are writing your OpenSCAD script.
Use 'knurledFinishExamples.scad' to start playing with this library.