Ubuntu

General

update-rc.d -f mysql remove

... removes mysql's startup script

Hacks

/etc/NetworkManager/NetworkManager.conf

... comment out dns=dnsmasq in order to preserve normal DNS behaviour

/etc/X11/Xsession.d/

... remove 70im-config_launch from this directory

rm /usr/share/sounds/ubuntu/stereo/system-ready.ogg

... remove the annoying startup sound in a brutal way