Havent ever seen one yet, but we always get kidded about glowing in the dark soooo...
A black t-shirt with a bunch of silouhets of people standing in a group and one person outlined in green with the caption under it,
"Can you pick out the Nuke Worker in this group?"
Or,
one side of a shirt with a normal looking persons head, a normal smile, and on the back the same head but with a huge brain bulging out, an evil smile on the face, and the electron rings around it with the caption,
front of shirt with normal head "A normal brain"
back of shirt with bulging brain "A brain on NUKE (or NUKIE)"