Create your graphic using layers in Photoshop. Assign the desired translucency to each layer. Greyscale works best so it works with any background pattern. This isn't a requirement though. You can get some interesting effects with color!
When you've got the picture complete, add a transparent pixel to each corner to identify the boundaries of the picture. Actually, only three pixels are needed to identify width and height. Place two of them at the top as they would be normally hidden by the menubar. The third pixel can then be anywhere along the bottom of the picture to represent the height.
Merge Visible Layers, Select All and copy. You now have the complete graphic in the clipboard. This can be pasted into the Scrapbook and then dragged to the desktop to create a clipping file. This clipping file can be used directly for your desktop picture or you can drag it onto my ClipDragon utility to convert it into a usable PICT file.
If you have admired the