Shush! is a very simple application that sits in the Windows Tray (the space next to the date and clock). When your computer locks, either when the screen saver kicks in or when you manually lock it, Shush! will mute all the audio outputs. Thanks to this, your coworkers won't have to listen to your music anymore when you walk away. It's a software created and developed by Eric Martel, licensed to you under the MIT license.