I've been obsessed recently with double exposures (and by extension silhouettes) for a few months now. My most recent ones are from Tori.
First off, we'll start with silhouettes...


Then we add some nature...
Then you do some Photoshop tweaks.....
I love how these turned out. Especially the one that looks like the tree is ice crystals.
(below images can be clicked to enlarge)