rofl0r
nat-tunnel
NAT Tunnel: to effortlessly serve from behind NAT
gnuboy
latest version of original laguna source, with a handful fixes for modern compilers and systems
jobflow
runs stuff in parallel (like GNU parallel, but much faster and memory-efficient)
concol
terminal wrapper library for ncurses with smooth 256 color handling, termbox, or a virtual terminal on SDL
debuglib
wrapper library for the functionality offered by ptrace. features facilities to enter breakpoint, debug and hook syscalls, etc.
df-mayday
patch to get mayday tileset into your current Dwarf Fortress folder. works on linux and mac, and windows with cygwin. In theory, it should also work with future releases.
endianness.h
simple public domain header to get endianess at compile time on a variety of platforms
hardcore-utils
some core unix utils with focus on simplicity and ability to build standalone.