When one is working with Photoshop layers, there are times when you would like to apply an effect to a composite of a layered image. One could flatten the image (after first saving it as a .psd image or .tiff image) but there is a better way. Select the current top layer in your Layers Stack. Then press Ctrl/Cmd + Alt/Opt + Shift + E and a composite is produced on its own layer at the top of the stack.. One can then apply an effect on this layer or you can copy the composite image to a new file. Since this composite is on its own layer it can easily be removed or made invisible.
While this tip applies to Adobe Photoshop Elements 9. It will work with some of the earlier versions of Elements.
Crtl/Cmd means Control Key on Windows, the Command Key on the Mac.
Alt/Op means the Alt key on Windows and the Option Key on the Mac.