Show All Windows for an App in Mac OS X with Mission Controls Exposé
Exposé was replaced with Mission Control in OS X Lion by name, but that doesn’t mean some of the most useful functions of Expose are gone, and in fact what you could see in Expose is still around in the newest versions of OS X, including Mountain Lion 10.8 and newer. One very popular feature was the application Expose feature, which revealed all windows for a specific app, and this is still around in OS X but it’s now visible through a gesture combination.
To access this app-specific Expose in OS X and display all of an applications open windows, move the cursor over an apps Dock icon and then do a three fingered swipe down. You’ll be brought to the familiar all-window view that was very popular in prior versions of the Mac.
Depending on your Mission Control and gesture settings in OS X you might need to do a four-fingered downward swipe instead. Performing the downward swipe in the currently open app has the same effect, assuming that app has more than one window open.
Update: for older Macs or those without a trackpad, you can access the same feature by using the keyboard shortcut Control+Down Arrow.