Project Guest VM sounds interesting, a JVM written in JAVA running on
Xen with a microkernel written in C.
http://research.sun.com/projects/guestvm/
http://www.youtube.com/watch?v=iHIaH12f2Ek
Perhaps by using etherboot:
www.etherboot.org
http://etherboot.org/wiki/soc/2008/stefanha/journal/week10?s[]=xen
One could boot Xen + GuestVM + River etc, using gPXE (network booting
via an eprom on the network card).
This might be used as a distributed compute farm, or for generic network
device hardware, who knows?
Just thinking about future possibilities, thought I'd share.
Cheers,
Peter.