Apollonian Circles

I am a geometry nut. I used to make stuff like this all the time. I love the complexity of how these circles interfere and seem 3D.

Initial set of circles with 90 degree separation (4 sets)

Same but thicker lines

60 degree separation (6 sets)

My source code for these is in java and will print direct to a printer. I'll send it to anyone that is interested.

Some interesting reading:

Source Code for above
Apollonian Circles (Wikipedia)
Apollonian Circles( Google Images )
A Tisket, a Tasket, an Apollonian Gasket