A friend of mine sent me this link to a wonderful PBS series on fractals. If you are unfamiliar with fractals, I highly recommend you watch the program, it is not very long. If you have trouble watching it thru the last link then try this link where you can watch it chapter by chapter.
In particular, I recommend you pay attention to the section in part II on "The Monsters" by Georg Cantor; not only was it the first fractal Mandelbrot recognized when he studied noise in radio transmissions, it was the exact same pattern I first noticed when I started looking closely at health care spending data at multiple levels. And it is the same fractal pattern I have used in a power point I am creating to illustrate the fractal nature of health care spending.
And here is a wikipedia link on fractals