The bogof was once every grocer's favourite expletive. But as we report this week, it's falling out of favour, with half-price and save deals coming to the fore.

Is this a case of consumers wising up to the waste that's often synonymous with this form of promotion, as bargain hunters buy twice as much as they need?

Are retailers wising up to the dead storage space that a bogof entails? Or are suppliers saying no to a form of promotion that appears to have little long-term impact on sales?

You'll have to read the feature to find out. In the meantime, talking of saves, it's time to doff the hat, once again, to Warren Buffett, the legendary investor, who stumped up 20% of the cash Mars was looking for.

Wrigley is a gilt-edged investment if ever there was one. And capitalising on the credit crunch, he's picked up his stake at half price. No buy-one-get-one-free nonsense. Just a simple half-price mechanic.

And it's also vaguely comforting that he prefers simple propositions such as chewing gum rather than complex financial ones.