It's literally on the YC application form.

"He said to ask about a time when they'd hacked something to their advantage—hacked in the sense of beating the system, not breaking into computers. It has become one of the questions we pay most attention to when judging applications."

The part about "make tons of money" isn't there, but I don't think anyone disagrees with that part -- YC recently launched a separate branch to handle nonprofit ventures.