What are your Favorite Text-Processing Tools?

I. Love. Text-processing.

I don't know why. Don't ask me why. It's weird. But if it's a markup language, templating engine, static site builder, converter, generator, pipeline, etc., it fills me with pure joy to use them and learn about new ones.

So, I want to hear from you. What tools do you use? What's your favorite markup language? What's so good about Asciidoc, or Org-mode, or Flnerb? Why is your static site builder the best? What simple command line utility have you super charged by duct-taping shell scripts all over it in order to handle your most extensive text-file-conversion needs? Show me your shell scripts! Your one-liners!

Bonus game: let's see how many people come here after seeing the title without reading the post or the other comments to say "Pandoc."

Bonus score as of 10/25 8:20 AM PDT: 1