Because of its lighter taste, grain whisky has typically been used only as a bonding spirit in modern whisky making, to unite and round out the various single malts included in a blended scotch. But more than 100 years ago, grain whisky was a popular and inexpensive drink on its own. Unlike single malts, which are usually pot distilled, grain whisky is column distilled (hence its lighter flavor), generally uses unmalted grains, and combines whiskies from a number of distilleries. This subdued spirit is now getting a major worldwide boost thanks in part to the efforts of the spirits giant Diageo, which has relaunched Haig Club, an old brand redefined to reach a new audience—helping spur many whisky aficionados to rediscover grain whisky. Here are four of the best examples.