A Woods Lamp - always useful when you're lost in the forest right? I'm just kidding! I think it has something to do with the skin and UV light. Sounds like something I saw at a rave in Brooklyn a few years ago. Anyways, they've been moving here a lot at Pure Spa Direct and I thought you should know about it... why? I have no idea... I'm just a shipping guy! See our great Wood's Lamp selection HERE!