the one in my avatar I did using men's shirts. I used a plain center for a signature square, but you could use a shirt square instead (either same as the corner squares or a 4th block). I drafted the block myself, but I'm sure someone somewhere has written a pattern for the block :-). I made a 9" puss in corner and then used that as the center in a 15" puss in corner block. I quilted the individual blocks and then put them together using sashing - so your sashing size could easily vary if you don't do it QAYG. Here's a link to my original post about it:
http://www.quiltingboard.com/picture...s-t131269.html.