Sonic Youth need no introduction. Absolutely one of my favorite bands of all time. This photo above was taken when they played Daydream Nation in Melbourne at the Metro. It's not that unusual to see them do a but of guitar porn like this.
However, I do have some bragging rights about the photo below. It was taken at the Corduroy Records building when Lee Ronaldo, Thurston Moore, Steve Shelley, and Jim O'Rourke (active member of SY at the time) were invited to record an improvised live-to-acetate recording for Saucerlike Records. There was a limited release of 800 copies, with the cover art done by Kim Gordon.
The band had just come off the plane, so Kim was too tired to join in. The guys didn't have their own equipment, so they borrowed everything. This is Thurston playing on the recording, using my beloved Japanese guitar, a Suzuki Super-Sounds!