Billy Mays, most well-known for his OxyClean commercials, died in his sleep last night, according to the Discovery Channel. The spokesman was 50 years old. Discovery Channel issued the following statement: "Everyone that knows him was aware of his larger-than-life personality, generosity and warmth. Billy was a pioneer in his field and helped many people fulfill their dreams. He will be greatly missed as a loyal and compassionate friend. Our deepest sympathies go out to his family at this time of incredible loss." An episode of Mays' Discovery show, Pitchmen, airs tonight.