Deviant Art user minidelirium has created some of the most intricate papercraft art I've ever seen. She has created crafts of all sizes from a mini Kupo to a huge Zelda model. You should definitely check out her profile and look at the progress photos and more detailed shots of the characters.
Wow! That's what comes to mind when you see the hand-cut paper art of Joe Bagley. Each design is hand-cut from a single piece of black paper and mounted to an acid-free white mat board. The intricacy and details of each design are astounding. If you want one, you can buy one of his designs on Etsy.
Raise your hand if you ever found folding origami to be incredibly difficult. Now lower your hand, and drop your jaw because these paper origami by Anja Markiewicz will blow your mind. Each piece uses paper smaller than an inch and width. If you thought you were getting good at origami, think again.
I am absolutely floored by the illustrative art of Brittney Lee. All of her illustrations look like they were plucked straight out of a Disney animated movie. From the character and background illustrations, to the details and colors, everything matches the quality of the most impressive Disney animation. She has even created some paper art that you can catch at the bottom! If you like her work, I highly suggest purchasing something from her Etsy store.