OK, this one's a doozy and quite complex in it's stupidity:
I was at work a while ago and talk came round to the attack on the twin towers.
Colleague 1: It's the 4th anniversary of the attack tomorrow. It scary how long ago it was..
Colleague2: Is it September already..? Christ, that's another year gone.
Dumb chick: It's not the anniversary in the UK though.
Colleague 1: ...what..?
Dumb chick:It's the anniversary for them, not for us. We don't celebrate it for another 2 months.
Colleague2: (dumbfounded). And how the fuck do you work that out?!
Dumb chick: Well, it's the time difference, innit. And they work their calender different to ours.
...
There was no one who was going to point out everything that was wrong with her theory.
Needless to say she didn't last too long.
I was at work a while ago and talk came round to the attack on the twin towers.
Colleague 1: It's the 4th anniversary of the attack tomorrow. It scary how long ago it was..
Colleague2: Is it September already..? Christ, that's another year gone.
Dumb chick: It's not the anniversary in the UK though.
Colleague 1: ...what..?
Dumb chick:It's the anniversary for them, not for us. We don't celebrate it for another 2 months.
Colleague2: (dumbfounded). And how the fuck do you work that out?!
Dumb chick: Well, it's the time difference, innit. And they work their calender different to ours.
...
There was no one who was going to point out everything that was wrong with her theory.
Needless to say she didn't last too long.