Tuxdoc
In my game 'tuxmino', users can create gamemodes written in Lua. The game iteself however is written in C and all the lua functions that users can call are actually written in C. I needed a simple way to create lua function documentation from C source code, and so I created tuxdoc. Tuxdoc takes a docstring like the one below and converts it into html.
/*
* lua function
* @brief a brief description of the function
* A full summary (can be multiple lines).
*
* @param parameter_name This is how you specify function parameters.
* @returns type
* @usage example_function(parameter_name)
*/