Uncommon Brewers: Bacon Brown Ale (Credit: Craft Cans)

In a simpler era of brewing, beer was composed of just four core ingredients. Armed with water, hops, grain, and yeast, brewers created a range of unique ales and lagers, from bitter India pale ales to chocolaty stouts as dark as December night. But as the craft beer movement continues to grow and evolve in America, madcap brewers have begun to explore the far fringe of flavor. They're making beers with offbeat ingredients such as algae, fungus-infected grapes, bhut jolokia peppers, and even bull testicles. (Because why wouldn't you?) And though the beers seem like a game of double-dog dare, the oddities remain surprisingly drinkable. Here are 10 of our favorite strange brews in America.

Freetail Brewing Company: Spirulina Wit

Come St. Patrick's Day, drinkers across the country toast with green beer. They do the same down in San Antonio, but instead of dyeing beer, this experimental brewery incorporates the vitamin-rich, blue-green algae into its Rye Wit, an aromatic Belgian-style witbier. The algae add notes of tropical fruit, meaning drinking to your health is equally delicious and nutritious.

Short's Brewing Company: Key Lime Pie

At first blush, the beers from Short's Brewing seem like a high-concept joke. What else can one think about Pistachio Cream Ale, PB&J Stout, and Strawberry Short's Cake? But these weirdos work, none better than Key Lime Pie. Graham crackers, marshmallow fluff, and fresh limes conspire to create a tart-and-sweet treat that won gold at 2010's Great American Beer Festival.