Very interesting! I am planning on making both my boys couch quilts for xmas this year... this would be a fabulous idea for the backing!
I found an online code generator
http://www.the-qrcode-generator.com/ I did it for their names and birthdates. It's neat to see how when you start adding their interests how much the pattern changes. I think I'll do mine in scraps more or less.
Now that I have the codes, I just need to graph it out. It should actually be fairly easy. I figure start below the corner squares and do them row by row then fill in the top and bottom after I have the rest done.
I'm so happy I looked at this thread! I really wanted to do something interesting and unique. This will definitely fit that bill and they'll both love it!