Here's how you can quickly pull up the Dock even if you're running a full screen application in Mac OS X Lion. 1. Open the application you want to run full screen. 2. When in full screen mode, swipe twice at the bottom of your Mac's screen. 3. The second swipe will make the Dock appear and you can then access all of the application icons that are on your Dock. This is quicker and easier than having to move out of full screen mode to see the Dock again in Mac OS X Lion.
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Show the Dock in Full Screen Apps in Mac OS X Lion | OS X Daily