Deprecated: FreeBSD as a PV DomU
FreeBSD has gotten Xen support in fits and starts over the last few years. An internet search will show a port of FreeBSD 5 to Xen2, freeBSD 7 to Xen 3.0.2 and some chatter about support in 8-CURRENT.
Now, to the best of my knowledge, most of the work for all of these was done by Kip Macy. (thanks!)
Ok, so down to business. There is talk that Mr. Macy has gotten support for running FreeBSD 8-Current i386PAE as a DomU in 8-current http://unix.derkeiler.com/Mailing-Lists/FreeBSD/current/2008-08/msg00551.html so, this page will document how to actually set this up.
First, if you don't alrealdy have an 8-current i386 box about, you need to install one. ftp://ftp.freebsd.org/pub/FreeBSD/snapshots/200809/8.0-CURRENT-200809-i386-disc1.iso is what I'm using, but you probably want to use whatever is latest.