When I was younger I was trying to learn the traditional unix tools, so I sat down with a copy of openbsd and made a wiki using only what was found in the base system, and perl was cheating. The templating engine was m4, web server in shell, page history in rcs, a really neat back reference system in awk(when you square linked to another page, it would put a link back in the backreference section of that other page, inspired by everything2) ...
Now I am trying to see if I have any of the code saved... It was probably one huge pile of injection vectors... but they were my injection vectors.
Hah, found it, Apologies for inflicting it on everyone, But I was having too much fun trying to figure out what past me was on.
Personally I find it quite reasonable for code that you don't plan on changing any time soon.