Here’s a great tip I just read over at CrunchGear. Using a hidden setting you can switch tabs in Firefox by making a twisting motion with your fingers. This will only work if you have a multi-touch surface like the trackpads on newer MacBooks. You will also need to make sure you have the latest version of Firefox.

To change the setting, just type about:config into the address bar. A warning will appear telling you that these are advanced settings. Click the “I’ll be careful, I promise” button to continue. Don’t worry about breaking anything, you can right-click and choose reset on anything you change.

Type “twist” into the filter box to filter down to just the settings we want. Find browser.gesture.twist.right and double-click on it. Change the value to Browser:NextTab. Do the same for twist left, but use Browser:PrevTab instead. The gesture should work right away. Try putting one finger down and rotating another around it.

If you find that it is a bit slow to respond, you can change browser.gesture.twist.threshold to a lower value.

Changing the filter to “gesture” will let see all the other gestures that are available. Pinching is set to zoom, and swiping is set to go back and forward. You can change any of these to do something else if you want. For example, the twist gesture is a bit awkward, you might prefer to have tab switching set to the swipe gesture instead.

If you are looking for more settings to change in about:config in Firefox, check out this list.