Most people think of St. Valentine's Day as a time for lovers, but for crime buffs and those interested in gangland history the day will always be associated with a gruesome crime on the north side of Chicago in 1929. On that day gunmen, supposedly working for gangster Al Capone, used machine-guns to murder seven men from a rival gang. Civic leaders in Chicago would like to leave all that in the past, but people remain fascinated by the era.Visitors to Chicago can experience the light side of its nefarious past at Tommy Gun's Garage, a dinner theater featuring actors portraying hoods and flappers from the Prohibition era.In the 1920s and early 1930s, U.S. law prohibited the sale and consumption of alcoholic beverages nationwide. Gangsters, like Chicago's Al Capone, took advantage of the ban to make a fortune by supplying beer and liquor to the public through a clandestine system.Rival gangs fighting over the illicit profits killed scores of people and tarnished the reputation of...