Some years ago, I had to photograph academics doing their thing. I found a print of the job recently, and thought the formula looked interesting. The main protagonist tells me:
"_The maths describes the clustering of high points in the density field. At the time, we thought galaxies might form there (in some circumstances, we still do)_."
And I watched him write it out, without his having to use a cheat sheet; you don't become Professor for nothing.
Also available "on dark shirts":http://www.redbubble.com/people/duncanw/t-shirts/1449260-5-its-all-greek-to-me.