Everyone loves toilets. Without them, the streets (and our children) would be covered in crap. And there's nothing quite like rushing to the toilet in a London Film Festival cinema and relieving yourself just before a UK premiere. But how observant are you when you're doing your business? Now you can find out with the LFF Toilet Quiz.

What do you get as a prize? Well now, if you've been following film folks on Twitter over the past couple of weeks, you will have noticed a ridiculous number of tweets about the free chocolate offered to delegates by the BFI. But looking at endless pictures of other people eating chocolate sucks. So we're going to give you the chance to win three whole bars of Green & Black's for yourself - plus one mini-chocolate bar too.

Now according to Tesco, each individual bar costs around £2.06. So together, this mind-blowing chocolatey haul is collectively worth over £6.18. SIX POUNDS AND EIGHTEEN PENCE. That's a lot of chocolate (warning: no it isn't). To get your hands on the chocolate, all you have to do is name the five LFF cinemas from the pictures of water closets below...

Email/tweet answers to This e-mail address is being protected from spambots. You need JavaScript enabled to view it (or @iFlicks) by midnight, Friday 28th October, and the person who identifies the most toilets wins the bounty. (Note: Bounty chocolate bars are not included in the prize.)

Official LFF venues:

BFI Southbank

Cine Lumiere 

Curzon Mayfair

ICA 

Odeon Leicester Square 

Odeon West End

Vue West End 

And here's the chocolate you can win:

Come on, people. Get flushing!