I forgot to install fortune when installing FreeBSD 9.1.

Here’s what I did to remedy it. I assume you have already downloaded the img.

chmod 666 FreeBSD-9.1-RELEASE-amd64-dvd1.iso
su -
mdconfig -a -t vnode -f FreeBSD-9.1-RELEASE-amd64-dvd1.iso -u 55 
mount -t cd9660 /dev/md55 /mnt
cd /
tar -xvf /mnt/usr/freebsd-dist/games.txz
fortune