Roll out the barrel and we'll have a barrel of fun. That line made more sense back in the pre-metal keg days. Sadly, the days of coopers feverishly maintaining wooden beer casks have passed. But you can join brewing's fast-growing trend and put the romance of wood back into beer with barrel aging. Strong beers like barleywine and imperial stout are aged in used bourbon or other barrels for an added depth provided by a shot of sandalwood, cinnamon, vanilla, and whiskey.