Mute the Mac Boot Chime with StartNinja for OS X Lion

Macs have always had the classic boot chime that announces the system has begun startup or has rebooted, but if you’re in a quiet place you don’t always want that sound to play. You may know that you can temporarily mute the Mac by holding down the Mute key during boot or reboot, but if you are looking for a more permanent solution, check out StartNinja. A free and simple utility that gives users the ability to disable the startup chime, StartNinja will keep the Macs boot sound quiet while allowing the Mac to retain normal sound function otherwise.
For those running Mac OS X 10.6.8 or prior, holding mute works on a per boot basis, or there is a system preference panel that gives the same ability to disable the boot sound.
Thanks to vijay for the tip in our comments

Alternatively, you can mute your computer and after the restart/ new start you will not hear the chime.
lol… true
Is there a command line instruction that can do the same thing?
Awesome site.
Start ‘ninja’…good one
There is also “auto mute” auto-mute.com.
StartNinja is awesome! And it works!
Is there a way to change the boot chime to something else?
I don’t think , because chime is inside efi bios …
Nice utility, but not planning to use it..I love the boot chime!
I haven’t tried StartNinja, as I use Snow Leopard. However, “Psst” has been the most reliable program I’ve found, and it works in Snow Leopard or Lion:
http://www.macupdate.com/app/mac/16780/psst
I’m so terribly happy I’m still on Snow Leopard. StartNinja looks awful, just look at it. Since Apple made iCal and Address Book look ridiculous people seem to think they can do to the user interface whatever they like to do—as if they are on MS Windows.
Snow Leopard StartUp Sound’s aesthetics are much better, although not perfect either because of the way the credit line is crammed in.
Startup Sound preference pane sets a volume that applies only to the startup chime:
http://www.macupdate.com/app/mac/16425/startupsound.prefpane
I use it with Lion 10.7.2 and Snow Leopard 10.6.8
Make sure you download the beta, not the “latest stable release.” The “stable” release installs, but won’t work on an Intel-based Mac. Neither will the uninstaller.
Did not work on my iMac.
it did not work on my Mac Pro
Why would you want to do this? The whole point of it is to tell you if your mac is working correctly.
some people travel Alex, and some people run studios. you can always if it passes boot procedure by the Apple logo and spinning wheel.
[...] Via | OSXDaily [...]
You really do need to turn it of when working in a library, or trying to take notes in a lecture, or just trying not to wake someone up.
[...] home – for OS X 10.6.8 StartNinja – for OS X 10.7 Lion and later stLight.options({ [...]
Installed Startninja on my Mac 10.7.4 and it doesn’t always work
once in a while the chime would still go off again and wake up the whole neighborhood. Very annoying…
[...] the Terminal, you’ll be better off using the one-off Mute key approach or using a simple tool like StartUp Ninja to silence the sound. StartupNinja is basically just a GUI frontend to the nvram tool discussed [...]
Both utilities (StartNinja and post) work on my iMac with OS X 10.8.2 (Mountain Lion). But only if I have not plugged in the headphones. If I have headphones plugged in, the iMac plays “ta-dam!” on boot. And it plays it from internal speakers!