Customizable grid spacing on the Desktop!
This is a Leopard only tip. If you bring up the View Options with "Command - J" or by choosing "View" and "Show View Options" in the Finder, you will find out that it got many new features in Leopard. One of them, when you are on the desktop, is Grid Spacing. I think that is really cool because it has always been something that bothered me (I used to think the way icons are displayed is better on Windows, not anymore!). I think the way it is by default puts the icon on the desktop not close enough to the edge. When you have multiple rows, I think the spacing is a bit too large. By adjusting the grid spacing, you will also be able to have more icons on the desktop before it looks cluttered. Here is an example: