My former vocal coach, Judy Davis (coach to the stars) http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2001/01/31/MNL126003.DTL
always recommended using Mustard Plaster for singers to clear up congestion (colds/coughs). Sinatra, Garland, Streisand, and Eddie Money all followed her advice with great success. As strange as it may sound, it really does work! http://www.pinewoodkarate.com/lessons/lesson12-31-99.htm

- Scott