I love the abstract and colorful look. It actually is really nice without being based on code! Some more code samples for people to click through could be fun to play around with too. Have you printed one for yourself yet? A photo of you wearing a shirt would be wonderful.
dojo4 [1] (Boulder, CO) built and subsequently took down a similar product called Speakteesy [2] last year. It's really hard to get the pricing reasonable, show people definitively what they're going to receive, and get a quality shirt. We did our best by generating a to-scale proof image using ImageMagick that a user would see prior to paying, but it wasn't a huge help. Lastly, the shirts.io [3] service was our fulfillment backend and, barring some light documentation in areas, was great to work with.
dojo4 [1] (Boulder, CO) built and subsequently took down a similar product called Speakteesy [2] last year. It's really hard to get the pricing reasonable, show people definitively what they're going to receive, and get a quality shirt. We did our best by generating a to-scale proof image using ImageMagick that a user would see prior to paying, but it wasn't a huge help. Lastly, the shirts.io [3] service was our fulfillment backend and, barring some light documentation in areas, was great to work with.
Good luck!
[1] http://dojo4.com/ [2] http://speakteesy.com/ [3] https://www.shirts.io/