I have to say that I "cheated" when I came up with this sketch....I saw a similar design on the front of an informational magazine and thought it would make an interesting layout.
The cool thing about this design is that you can make the squares whatever size you want. It's a 12" x 12" single layout and in this example I used 3" squares throughout.
Now, the 3" squares that surround the four pictures can be (1) patterned paper blocks or (2) other pictures that have an opaque layering on them that make the main pictures stand out even more (see example here).
Now, if this format isn't your favorite, then all you have to do is vote for the Sketch of the Week!! Right now, the front runner is a 12" x 12" double page layout. I count the votes each week and whatever layout format has the most votes wins - all you have to do is vote! Happy Scrapping!