It is in fact - it is called The BSD Hypervisor [1] and so far it exists only on FreeBSD, and this is where it was born. There are some forks to port it to other platforms (like Joyent's SmartOS) but they're closed and not out yet.
I consider technology awareness, competition and diversity a very good thing, therefore I think its important to mention FreeBSD in this case (and other BSD's too in other cases).
By the way, have you donated to FreeBSD [2] and OpenSSH [3] yet? ;)
