antiYomip

Note that each of these is covered by the GPL. Read that here.

In Ruby
Source
In C
Source
In x86 assembly (for NASM): It require file.pdb as input, and outputs FILE.GZ
Source
You can also copy the contents of the following file to your clipboard and paste it to a command-prompt in Win32. It will generate the antyomip.com file that would be compiled by the above antiYomip.asm: antiYomip.txt