Control startup sound volume
StartupSound.prefPane allows you to edit the volume of the startup sound, without changing the volume of your mac. For example if you mute the sound before you shutdown, so you don’t have to listen to the annoying startup sound, now you need not bother.
You can access these controls by going to System Preferences and then Startup Sound.
Download StartupSound.prefPane (PPC)
StartupSound.prefPane (Intel) (BETA)