One year at the Ponterdawe festival, I had nackered my voice during the evening pub sing (too much smoke, and not enough beer?). The next morning, we (The Boarding Party) were scheduled for an early set, with Jim and Johnny. When I showed up in a whisper, Johnny proclaimed, "I've got just the thing for you." He left the tent, and returned with two cans of Guiness and the following instructions: "Drink one now, and open the other just before the set begins. Sing softly at first, and keep sipping on the second can." Darn if it didn't work, and by the middle of the set, I could sing at full throttle (not his full throttle, but mine).