A very impressive cryptic
A couple of years ago, knowing my interest in the Penrose "kite" and "dart" tiles, my friend Derrick gave me a paper copy of this cryptic crossword puzzle, photocopied from "The Enigma", the newsletter of the National Puzzler's League.
(If you've never heard of cryptic crosswords, you may not want to start with this one. The NPL has a nice guide to solving cryptics, and you can find puzzles of this sort all over the web. There are three cryptics every month in Games magazine, and there's a nice introductory book on them, too.)
For one reason or another, it took me until quite recently to finally get around to attacking this puzzle. It's pretty hard (or at least I found it so), but quite remarkable for its many layers of complexity and constraints. I recommend it to your attention (and, if you solve it, I have a couple of questions for you).