Clean Desk for Mac

From Freak Software:

Clean Desk is helpful for graphics designers, page layout designers, web masters, gamers, and anyone who constantly switches between screen resolutions. If you've ever switched resolutions, you've probably noticed that some of your icons will tend to move over a pixel or two. This gets highly annoying when your desktop is tightly grided and pixel perfect.

The solution to this is Clean Desk. Clean Desk will 'Remember' the positions of the icons (on your desktop) that you choose. Then whenever you change resolutions and your icons have moved, you simply run Clean Desk (or use the include Control Strip Module), click "Restore Positions" and your desktop will automatically look the way it did before.