Wanna clone a debian installation real quick? Try:

# dpkg --get-selections \* > ~/dpkg.selections
# dpkg --set-selections < ~/dpkg.selections
# apt-get install dselect-upgrade

Or how about installing Fedora in 3 steps?

# rpm --root /fc7/ --initdb
# rpm --root /fc7/ -ivh --nodeps ftp://ftp-stud.fht-esslingen.de/Mirrors/\
fedora.redhat.com/linux/core/development/ppc/os/Fedora/fedora-release-*.noarch.rpm
# yum --installroot=/fc7/ -y groupinstall Base

(the latter is from Arnd Bergmann in <200703190134.26030.arnd@arndb.de>)