It's called Grimbergen and it's magical. Originating from the Norbertine Monastery in the Brussels, Belgium suburb of the same name, the beer has been brewed for at least 400 years. Michael Jackson (the beer snob, not Thriller) explains
The abbey of Grimbergen was founded in 1128... After being secularised during the French Revolution, much of the abbey was rebuilt in the 1830s, and it was further restored in the 1920s.
The abbey almost certainly had a brewery from its earliest days, and there are mentions of one in the 1600s. In the 1700s, there are mentions of wheat beers and abbey hop garden. Brewing stopped at the time of the French Revolution. When the abbey was re-established, beer was supplied by a local brewer, now long-gone. In 1958, the monks asked the nearby Maes brewery to make beer for them. In 1982, production switched to Maes' subsidiary ale brewery in Jumet, Charleroi, in the South of the country.
read more here.
I'm loading up on it as I start to put together my packing list to come back to the states. If you're nice to me, there might be one for you in my tweed suitcase...