Assembly knowledge and other useful knowledge of executables
GCC inline assembly quick tutorial
http://asm.sourceforge.net/articles/rmiyagi-inline-asm.txt
x86 and x86_64(AMD64) references
http://developer.amd.com/resources/documentation-articles/developer-guides-manuals/
http://ref.x86asm.net/
System V ABI ELF (Executable and Linkable Format)
http://www.sco.com/developers/devspecs/gabi41.pdf
http://www.sco.com/developers/gabi/latest/contents.html
http://www.sco.com/developers/devspecs/abi386-4.pdf
Post more if you have it!