neutron

[zaccone]

 This neutron walk's into a bar and ask's the bartender  for a drink , the bartender give's him a drink and start's to walk away , the nutron stop's him and say's, how much will it be for that drink. The bartender look's at the neutron and say's, for you no charge!

[rlbinc]

That must explain why they hang out in water holes.