Here's how to turn off the annoying beep that Facebook recently starting making when you get a new notification:
1. Click on the gear in the upper right corner
2. Choose Account Settings
3. On the left side of the screen, click on Notifications
4. In How You Get Notifications/On Facebook, click View on the right
5. Click to remove the check mark in "Play a sound when each new notification is received."
6. Click Save Changes
Presto! No more beeps!
Read my book Virus of the Mind: The New Science of the Meme