Regarding the Pepsi / Coke test I'm a bit surprised... Apparently the letter 'M' and 'Q' were inducing people in error because people prefer M over Q.

But... From personal experience I can tell if coke is coming from a 20cl glass bottle (or a 33cl can) or a 25cl plastic bottle / 1 liter plastic bottle (tried with friends several times, they're always amazed). I can't differentiate 20cl glass from 33cl can and I can't differentiate small plastic from big plastic. But, simply, coke in plastic bottles doesn't have the "coke" taste. It just doesn't.

There's no way on earth you can make me drink Pepsi and I'll say it's coke. If often happen in restaurant: I ask if the coke they have is real coke. Typically people don't like but sometimes they do and serve me Pepsi. Than I get mean.

: )