See Hurd about the expansion of the "Hurd" acronym.
The GNU Hurd is the GNU project's replacement for the Unix Kernel. The Hurd is a collection of servers that run on the Mach microkernel to implement file systems, network protocols, file access control, and other features that are implemented by the Unix kernel or similar kernels (such as Linux).
Check out the Hurd wiki at 
http://hurd.gnufans.org/bin/view/Hurd/WebHome or the main page at http://hurd.gnu.org
Quote: "In short: just say NO TO DRUGS, and maybe you won't end up like the Hurd people." -- LinusTorvalds
