What is you favorite recording/performance that was never officially released by the artist or his/her record company? Examples could be live simulcasts, live recordings sold directly after the show by bands, or boot legs and concerts up on the Internet music archive (for all you deadheads out there). Evenings, when the band was performing at the top of there game, In a great sounding venue, that just leaves your head spinning after you hear it.
Mine would have to be Bruce Springsteen Live at the Main Point, recorded and broadcast live in Philadelphia on FM radio in 1975. It was a benefit concert for the Main Point coffee bar. Bruce was in the studio working on "Born to Run" at this point in time, and he was still hammering out the music and lyrics for some of the songs which would become his most epic album. Thunder Road for example was a work in progress, and is referred to as "Wheels for Wings" in this performance. I listen to some of his performances during this show and can hear what he was trying to accomplish on certain tracks on his previous studio album "The Wild and the Innocent". Just a fantastic show, It's up on the net in various torrent's for all you Boss fans. Highly recommended.