I got this idea from the Creating Keepsake October 2008 magazine issue. If you have this issue look at pages 69-73. If you don't have this issue you will find the directions below. First of all this challenge can be a bit time consuming but I had alot of fun with it.
Step 1 - go here for the templates & print off the one you want to use. After printing the template you will need to enlarge the template. I believe I enlarged by 140% on my printer. You might want to make two copies of the enlarged print so you can have one for the "mat" and one for the photos.
Step 2 - Cut your photos in the shape of the grey part of template.
Step 3 - Finish your page as you wish.
You can find the original challenge I posted on Split Coast Stampers.