Hyperlisp!
I made a simple Lisp lexer/parser in C as a coding exercise, and decided to create HyperLisp! using it.
HyperLisp!™ is a preprocessor that provides a 1:1 mapping of HTML to Lisp syntax. You can find the source as well as a quick guide on the GitHub repo. If you don't want to bother compiling it, you can try out the online demo powered by Emscripten.