"If you think these are weird, you should see what I’m going to put on when the sun goes down," Avi says. He rummages in a bag and pulls out a contraption that looks like a pair of glasses without lenses, with a dollhouse-scale light fixture mounted above each eye. A wire runs down to a battery pack with belt loops. He slides a tiny switch on the battery pack and the lights come on: expensive-looking blue-white halogen.