Bogof learned this week that the Zubrowka vodka bottling plant in Poland is equipped with a state-of-the-art cleaning machine that washes out bottles with, believe it or not, vodka.

What isn't clear, however, is whether the company is using its own vodka for this process or a rival's. Wouldn't that be the ultimate in brand denigration?

You can imagine the endorsement: 'It may not be fit to drink - but it leaves our bottles sparkling.'

I wonder, too, what happens to the effluent resulting from this exercise. Does Poland have the world's most potent sewage network? Do residents feel lightheaded every time they flush the loo?