In Frank Bruni's review of Belgian restaurant Resto he mentions one of the more than 50 beers served: "Order the Kwak, a beverage and a puzzle in one. If you don’t remove its hourglass-shaped goblet from a wood cradle at just the right angle, you go thirsty. And if you don’t return it to the cradle just so, it goes horizontal."
A tip for Frank Bruni and anyone else unfamiliar with Kwak: it's perfectly acceptable to keep the glass in the cradle, raising the cradle and glass together to drink.
And there's a reason for the unusually shaped Kwak glass. Kwak was first brewed in 1791, in the days of the stage coach. Stage coaches would often stop at an inn for refreshment, but the coachmen were required to stay with the coach and horses. So that coachmen wouldn't have to go without, Pauwel Kwak, an innkeeper, had a special glass created for his beer. The shape of the glass enabled it to be hung on the coach and be easily held in a thick glove.