Source for my profile picture in TikZ (also my first bounty anywhere on Stack Exchange)

Any code of mine that I publish anywhere on stackexchange.com I hereby place in the public domain to the extent governable by law. Explicitly, I place it under the CC0. This also applies to documentation/instructions etc.

Opinions I post are mine and mine only unless clearly stated.

Attribution (especially if I say anything clever) is appreciated where reasonable - but specifically not demanded.