Whether you want to launch an application when your computer goes idle or you just simply want to mute your speakers that way when you leave the office your email notifications do not annoy your fellow coworkers, System Silencer can help. System Silencer has a set of stock toggles such as turning off your monitor, muting your sound, and locking your workstation, all of which can be activated by your computer sitting idle for a specified number of minutes. This is a really nice program and works on most Windows based Operating Systems.
