The music of Smashing Pumpkins got me through some very dark times as a teenager, but finding out he hates me because I'm gay snapped that personal connection. I'm usually able to separate the art from the artist and still enjoy good stuff made by bad people, but I'm not able to enjoy them anymore. The connection was too personal and the betrayal was too great.
Billy attempted to sell an Alesis SR-16 that was used in his band for $30k. It's a $100 drum machine. He was selling it himself. No charity or anything; he just tried to hyper-inflate a very common drum machine that is still produced because he thought he added that value to it by owning it. That was pretty weird.
I mean, in the sense of music history it is worth more than any other random one you can find on the street. But maybe somewhere around $500 - $1000 if it was signed by the band.