Ok, have you heard of this "stamping a layer" thing in Photoshop CS??
If no, well, let me tell you about the beauty of this command.
Let's say you are working on several layers and you want to merge the layers and experiment with levels or make changes, but you don't really want to loose those layers as separate layers in case you need to make changes.
Now, you could make a copy of each of those layers and then merge them, but that's tedious.
Instead, use the Stamp Layer command. Have only the layers you want to duplicate as visible layers. Then hit control-alt-shift down at the same time, holding those down, hit e.
Magically you will get another layer with all the layers you have visible merged into that layer, but your old layers will still be there! Separate, not merged!
You'll have to forgive my bad explanation of this. I know this could be stated in a much more concise, clear manner. But I spent several hours out in the sun and my brain hurts. There's a post on the forum by Robin and this is explained by her, in those concise words you want.
I'm seriously rethinking my idea to limited edition Halloween wings. I started to run some numbers and I'd have to charge a ridiculous amount for the wings in order to make my time back, even excluding a profit. So I think I will do some Halloween things, just not with the exclusive tag. I'm working on some Halloween fashions now, with wings to follow. Weee!