(born March 26, 1968) is an American rock musician. He is best known as former guitarist and co-founder of the alternative rock band the Smashing Pumpkins and for his eclectic musical projects of recent years, most notably being a permanent fixture of A Perfect Circle. He was most recently a member of Tinted Windows, a 1960s/1970s inspired group with members of Cheap Trick, Fountains of Wayne, and Hanson.