I was playing around with the Facebook Timeline cover images and noticed that you could hack the cover image updates. First you need to change your profile to allow for the new timeline. I followed the instructions here http://mashable.com/2011/09/22/how-to-facebook-timeline/
Then select an image that would fit nicely across multiple tiles. Mark sections of the image in the same proportions as the Facebook timeline. Use a large picture to ensure the quality is decent when it become your cover image.
The crop and cut the image to the dimensions of each tile. Save each file separately, noting the order.