Makin' these shots!
1. Get the shots together in Photoshop.
2. Copy and paste the 'closed' image over the 'open' image and line them up. Now you have two layers, the 'closed' over the 'open.'
3. The erasor tool. This is what I prefer to use however if you want the entire 'closed' pic to be faded, as in the laptop above, you can fade the entire layer out with a filter, I think.:scratch: You can use the erasor for the whole thing, just remember that if your Opacity (top center in Photoshop) is set to anything lower than 100%, everytime you erase something, at 50%, for example and let go of the mouse button, then click it again, you will be erasing what you just erased by another 50%. Go ahead and experiment, Crtl + Alt + Z = Undo.
4. When using the erasor, you can set size, style and strength. Arrow points to style, the size can easily be changed by moving the slider at the top of the box. For this pic, I used the fuzzy lookin brush at 200 pixels and 4% opacity. The 4% opacity means I had to erase several times to get a clear view of what was beneath. Also note for this pic, I had to go to the 'open' pic and erase the open top thing. I used a paintbrush with the backround color so it would blend nicely. And you're done, hopefully...
Now just merge your layers together (Ctrl + Shift + E) and you can save as a .JPEG.
I use Photoshop 7.0.