[gregschlom]

The ASCII art (well technically ANSI art) histogram is neat. Cool hack to get something done quickly. I'd have spent 5x the time trying various chart libraries and giving up.

[Retr0id]

On a similar note, I like the crude hand-drawn illustrations a lot. Fits the "napkin" theme.

[smartmic]

Here [1] is a nice implementation written in Awk. A bit rough around the edges, but could be easily extended.

[1] https://github.com/stefanhengl/histogram