Call me self indulgent - but just for the heck of it, I have had a go at creating the first Light Art tee-shirt using Redbubble.
They don't work out to be what I would call cheap at customised low volume, at about $33 for 'T's' and around '$54' for hoodies BUT they do have enormous cache and will no doubt one day have some sentimental value to those of you who have walked the path and put up with my whims and delinquencies. They are also available as a longsleeve T or a soft cotton 'Hoodie'
You can purchase online from anywhere in the communicating world in a range of colours and a couple of styles:
http://www.redbubble.com/people/ozjohnson/t-shirts/4944432-1-light-art-photography-forumHere is a sample. The small text reads "Find Art in Light, Texture & Form"