Walgreens caused quite a stir late last year when it released its own exclusive brand of beer: Big Flats 1901 Premium American Lager. The low-cost beer --it goes for about 50 cents a can -- has gone over well with customers. So well in fact that the pharmacy chain plans to introduce Big Flats Light this summer. "Trial is high among our shoppers and repeat purchases are growing," company spokesman Robert Elfinger said in an email. "Because of today's economic situation, shoppers are interested in quality products with high value." Big Flats is made by the Winery Exchange in Novato, Calif., and brewed on contract at Genesee Brewing Co. in Rochester, N.Y. It's 4.5 percent alcohol by volume and has 148 calories. Retailer-exclusive beers are more common than you might think. Supermarket News wrote a story about the trend last month, including a mention of the Kroger Co.'s Port Republic brand. To read the full story, click here.