Glow in the dark marker ... more fun for drawing on your friends
Camp story (true): he (a friend) woke up after a <i>very</i>late night, had no idea we'd drawn humourous pictures all over his body (face, torso, arms, legs), tottered down to breakfast in the canteen, the windows were very small and the lights off so it was very dark ... 50-100ish people turned and stared at the glow ...

that was one of the most evil things I've taken part in ... it was immensely funny though, thankfully he found it quite funny too so we didn't get in trouble
Famous or Infamous?