So I just got my first ever Mac two weeks ago, and am still playing around with everything, trying to get used to everything. I got a wireless Mighty Mouse with the iMac, and am trying to configure it so one of the buttons is "Back" in my browser. So far, however, I have had no luck in making this happen. It does not seem to be in the Keyboard and Mouse options in System Preferences. If anyone could give me some help, it would be greatly appreciated. Thanks!