If you’re in a library or coffee shop you don’t always want that start up chime to play. Now you can silence the Mac OS X Lion start up chime with StartNinja. Free app StartNinja will silence your startup chime with just one click. If you want your Mac to stop chiming when you boot it up, open StartNinja and set the switch to “off”. StartNinja is a free download for Mac OS X Lion only. If your speakers and headphones are plugged in already then it will not work. It also doesn’t work properly in the iMac.