Re-usable AVR source code
The Atmel AVR is too small for proper C libraries, but I abstract some of my code well enough that it could probably be re-used. The AVR page has links and information about the ones I've published so far.
I have a big interest in service monitoring and supervision, mainly born from my frustration at how disfunctional many common systems are. (I'm looking at you, init scripts.) Daemonproxy is my attempt at producing a better tool than any out there. It needs some more work, but is already the service supervisor of my car project, running as process 1.
A good logger is priceless for debugging rendering loops and client/server communication. I've been very pleased with Perl's Log::Any. I've also written some modules around it. The logging page describes how this can be a great debugging aid.
Perl already has nice support for the OpenGL library. However, in order to create an OpenGL context you first need to use some other library like SDL, GLut, or Xlib. You need another library for things like textures or fonts. Also OpenGL is a bit verbose, so I wanted some helpful sugar functions to get the job done quicker. My OpenGL Page describes the way I solved these problems in a minimal way without dragging in a bunch of other libraries that would bloat my embedded system.