Conversation so far:
did Billy Corgan release any songs as a solo artist?
Billy Corgan released a solo album, TheFutureEmbrace, in 2005 and a collection of poetry, Blinking with Fists.
What is Billy Corgan's band Zwan?
Zwan was an American alternative rock supergroup that was formed by Billy Corgan and Jimmy Chamberlin, lead singer and guitarist, and the drummer of the Smashing Pumpkins
who else was in the band Zwan besides Billy Corgan and Jimmy Chamberlin?
Other members in Zwan besides Billy Corgan and Jimmy Chamberlin included bassist Paz Lenchantin, of A Perfect Circle.
is anyone else in the band Zwan besides Billy Corgan, Jimmy Chamberlin, and Paz Lenchantin?
Other members in Zwan besides Billy Corgan, Jimmy Chamberlin, and Paz Lenchantin included guitarists David Pajo and Matt Sweeney of various prior bands and projects.
what type of music did the band Zwan play?
Zwan was an American alternative rock supergroup who genres fell under alternative rock, pop rock, and power pop.

Question: when did Zwan form?
Self-contained rewrite: when did the band Zwan form?