Psst

Psst is a faceless application that lets you adjust/mute the volume of your Mac's startup chime. Double-Click "Psst!" in the Finder to adjust the volume settings.

Important: The method Psst! uses to change the volume does not work on every model! What it actually does: It simply adjusts the volume settings before shutting down and after logging in.

What is new in this release:

Version 2.1.1:

• Added check routine to prevent Psst from launching from disk image

• Psst asks you to anonymously submit your Mac configuration in order to create a comprehensive list of (un-)supported setups.
  Check it out here: www.satsumac.com/Psst/Compatibility.php
• Uninstalling Psst: just stop it and trash it!

Requirements:

Mac OS X 10.4 or higher