Last night, I had the privilege of sampling a 1996 Cantillon Kriek. It was really amazing - the years of aging had reduced the aggressive sourness, and allowed the sediment to settle to the point where the beer had an incredible clarity, too. I was a little surprised, in that everything I've ever read about aging beer seems to suggest that only high alcohol brews can withstand long aging times.
Has anyone else experimented with this? Is lambic more suited to aging because of its high acidity?