Smashing Pumpkins are one of a number of artists now allowing recordings of their shows to be freely distributed on the web via The Internet Archive (www.archive.org). Their 1995 and 2007 Reading Festival appearances are available. The 1995 set is from a radio broadcast, and there are two versions of the 2007 show, one an audience recording of most of the show, the other edited highlights from a radio broadcast. Here are the links:
1995 Radio broadcast
2007 Audience
2007 Radio broadcast