Slide Master View Shortcut key
At the bottom left hand corner of PowerPoint (bottom right for PowerPoint 2007), you will see 3 mini buttons. They are: Normal View, Slide Sorter View, and Slide Show. Now here's a quick trick. When you hover over these 3 mini buttons, hold down the Shift key. The mini buttons will now become slide master view, handout master view, and Set Up Show respectively. Thanks to Lucy from PowerPoint newsgroup for providing the useful tip!