Very tiny HI-TECH C program tiny.com compiles to 128 bytes!
Minimal run-time library. Good for tying in HI-TECH into other systems. You could even code BIOS parts in C this way! Well... maybe not.
Uses objtomac from mtrel, a bit of an offshoot of mixed. Introduces csup.rel (c support library) - can be used with libc and libf, but works without them. Yes, a bit confusing.. look at tiny.c