I found this image sometime last year and have seen it numerous times since.
It's Ellen DeGeneres' kitchen (Obviously, the image is from Elle Decor).
As far as the kitchen is concerned I don't like it; It is too industrial for me, but I do love the photo, and how it is made of many small prints.
It is incredibly easy to do so I had to copy it.
Do me a favor and ignore the shoddy photo quality... And yes, it does bulge out from the wall. Walls where I live are not straight or square. Or flat.
Simply cut/crop a photo into 6x4 pieces using Photoshop or Gimp or whatever you prefer, then take all the images to your local photo printer. Once printed, stick to a sheet of card or thin wood using double sided tape, or mount on paper and frame. Warning: the cropping does take a long time, depending on the size of the picture. Also, don't use spray glue. It doesn't hold very well.
This is a great, cheap method of showing off your photography (or in my case: Photoshop) skills.