I'm planning to make Quickie Tips a regular series. Whether it's Photoshop, Illustrator, or traditional art techniques feel free to contribute any neat or helpful tricks you've learned over the years.
Here's something I use frequently in Photoshop, New Window.
Tired of zooming in and out while you're painting in Photoshop? Just open another duplicate window resized to show the entire image.
Go to: Window-Arrange-New Window for yourfilename.psd
Tuck this new second window in the corner. You now have two simultaneous views of your work. While you paint in the main window the second window will show the changes too!