ZedZull
...
GingerBill created this collection of general purpose single-header libraries as well.
strangezak
Ah... Off the top of my head besides GingerBill's and the STB libraries there are no really good public examples of code...
Thank you for advertising my libraries!
Remotery from Don Williamson also comes to mind. It's a CPU/GPU profiling tool written in C that consists of one .h and one .c file.