For the first time it's possible to choose which kernel you want to use for the popular Linux distro Debian, either the Linux kernel, or the  FreeBSD kernel. This FreeBSD kernel support is added to both the "unstable & experimental" editions.

Debian distinguishes itself as cutting-edge by adopting FreeBSD & thereby sets a new example for an Operating System: a platform supporting 2 very different kernel technologies, with other aspects of the software remaining largely unchanged.  

Here's the anouncement from the developpers:

We just added two new architectures to the Debian archive. Everybody please welcome

  kfreebsd-i386 AKA GNU/kFreeBSD i386
  kfreebsd-amd64 AKA GNU/kFreeBSD amd64


Note that this enables porter NMUs for those two. In case you have a bug with a patch waiting for your package that has to do with one of them, please either fix it soon or expect a porter NMU to be done soon.

The two new architectures (well, better named OS i think, as they use a different kernel) are available in unstable and experimental. We do start out empty, importing only what is needed to get a build running. For this reason you will not be able to directly use it immediately. Please wait until they catched up, which I expect to happen soon.

You can read the original message here.