I was struggling with a similar dilemma this summer. I wanted to make a quilt for my son to take to college. The quilt could not be outdoorsy, sports, or dark colors. He is not at all into anything "manly". He's more the creative, drama, music type. He loves bright colors like hot pink, lime green, purple and orange. He didn't want a theme. Every fabric I put together looked too girly. He told me to stop looking at color as gender. I finally decided on a string quilt, which I'm still working on. I love the QR code idea. I found some "geek" fabric that I'm adding to my quilt that would make a really cool guy theme quilt. It has formulas, pi, mobius strips, double helix, etc. - would be a cool Big Bang Theory quilt.