Here's a neat twist on a concept that's been floating around the Web a while: "Camera and Pencil," in which artist Ben Heine appears to be holding a scrap of paper with a pencil drawing that perfectly merges with the real background, usually with some added bits of whimsy or fantasy. I like it! (Follow that link above to see more.)
I write "appears" because it's not clear to me how Heine does it. You're supposed to think that he sketched it on-site with incredible skill and held it to align perfectly for the camera. I dunno; maybe he did! But a much simpler method occurs to me: take a photo of your hand holding a blank piece of paper, then go home, do the sketch in perfect alignment and perspective, and paste it into the blank space with Photoshop. Or I suppose the entire thing could be assembled in Photoshop--the background elements, the paper, the drawing, the hand--but that would circle back around to being unnecessarily difficult.
To be clear, I'm not accusing Heine of "cheating." I don't really care how he does it--I think it's nifty and you can't spell "art" without "artifice" (wait, I have that backwards...). I just can't help speculating through the filters of "I wonder how he did that" and "If I were going to do that...." In any case, check out and enjoy the fun drawings.