An amazing new utility, Wuonm's Layers, changes all that. As with many other screenshot utilities, Layers takes a snapshot of your computer's screen at the press of a keyboard shortcut (by default, shift+option+S). But Layers' resulting image is jaw-droppingly different. Instead of a standard TIFF, JPEG, or PNG file, Layers' screenshots are files...with every item on your screen contained in a different layer.

Let me repeat that: every item on your screen--every window, every palette, every menu, every menu-bar icon, every folder or file on the Desktop, and even the Dock and the Desktop background for each of your connected displays--is a separate, editable layer in the resulting Photoshop image file. Even if you can't actually see an item, be it an icon on the Desktop or a window or palette hidden behind other things, Layers captures it and gives it its own layer.

For those who've never used Photoshop or layers, allow me a quick aside to explain. Imagine if a physical photo of a landscape was actually a stack of immeasurably thin transparency sheets, each containing a single item in that landscape--a tree, a rock, a bird, and so on. If you decided you didn't like a particular tree stump, you could simply remove its sheet and it would disappear from your photo. If a rock was in the wrong place, you could move it by sliding its sheet. If a bird's colors weren't as bright as you'd prefer, you could add a bit of color to that transparency to make the bird stand out more. This is--oversimplifying greatly--how Photoshop's layers work: you can work with each layer's contents separately from all the rest.

What this means is that if you normally process your screenshots in Photoshop anyway, using Layers means you no longer have to meticulously set up your screen beforehand. Instead, you just capture the screen whenever the urge hits you; later, you can move objects around and modify them, change window layering, and delete items to your heart's content.

I could go on and on about how extraordinary this approach to screenshots is, but Layers also has a good number of other useful features. On the simple side, if all you want is a traditional shot of the frontmost window, shift+option+F will give you just that (in PNG format, with window shadows). Alternatively, if you want to do some tweaking beforehand, pressing shift+option+I brings up Layers' Inspector window, which offers nearly as much pre-capture flexibility as its layered image files provide afterwards. (Each of Layers' commands--full screenshot, window shot, and Inspector--are also available via a menu-bar menu.)