I tagged along with my wife last Saturday night at a beer and wine tasting in Edwardsville. My wife went to taste wine and I went to taste beer.
At the tasting, they had one of my old favorites, La Fin du Monde from Quebec. In English, this translate to "the end of the world" and I suspect that if you drank a couple of these large bottles, it might be the end. La Fin du Monde is a high gravity beer. To make this beer, it goes through three fermentations. The last fermentation is done using champagne yeast which is one of the few yeasts viable at a very high alcohol content. Despite the high gravity, this is a light and fruity beverage. It is crisp for a high gravity ale, and is a great after dinner dessert beer.
One of the most interesting beers I tasted was another high gravity beer made by a company called "He'Brew". This beer was aged in rye whiskey barrels. It was quite strong (~10% ABV), but tasted even stronger due to the rye whiskey taste. Think of an IPA with a shot of rye. If you're a rye whiskey drinker who might want to moderate the amount of alcohol you imbibe, this might be a good substitute.