One of the design sites I've only recently encountered is It's Nice That, thanks to the fact that they commission art from the great Tom Gauld. They've just launched a limited-edition art book which looks great, and is based on one of those simple but great ideas I wish I could come up with.
A collaboration between illustrator Tom Edwards and designer/photographer Rob Matthews, Matthews explains it thus: "Taking a selection of Tom's drawings, I recreated them as photographs. This project plays on the idea of drawing from real life by turning it on its head." Click for bigger images.
As an aside, Rob Matthews has also printed Wikipedia as a book.