Go to HUD and type (windows key when on desktop):
startup
But there is not much by default. Ubuntu tends to hide most of the applications from the user.
To have the full set of applications that start on the system boot up go to terminal and use the following command:
which is as follows:
sudo sed -i "s/NoDisplay=true/NoDisplay=false/g" /etc/xdg/autostart/*.desktop
This will copy the whole list of applications to the startup list available via HUD startup software:
