Here's a great one from the source code to TeX. It's the beginning of section 1154.

The simplest math formula is, of course, ‘$ $’, when no noads are generated. The next simplest cases involve a single character, e.g., ‘$x$’. Even though such cases may not seem to be very interesting, the reader can perhaps understand how happy the author was when ‘$x$’ was first properly typeset by TeX.

Being a programmer myself, I most certainly can.

A noad, by the way, is what TeX calls (most of) the elements of a math list. (It can also contain nodes, which are what appear in horizontal and vertical lists.)

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