This one is coutrtesy of the landlord at my local:

There were these two blokes drinking in the pub, and the barman goes over to them and asks them what they do for a living.
"I'm a beekeeper," says the first one. "I keep bees"
"Really?" asks the barman. "And how many bees do you have?"
"Ten thousand" says the man.
"Right. And how many hives do you have for them?"
"Ah, five."
So the barman turns to the second man and asks "What do you do?"
"I'm a beekeeper too" he says.
"Ah, your not serious are ya?" says the barman.
"Aye," says the second man. "That's how we know each other - we both keep bees."
"Well, how many bees do you have?" asks the barman.
"About a million," says the second man.
"So how many hives have you got?"
"One. Fuck 'em."