Here's some that come to mind:
Without the album in front of me I can't remember the specific song - been a long time - but the live album, "Four Way Street" by CSN&Y has some real goodies.
"Child In Time" by Deep Purple
"No One To Depend On" by Santana
From Buddy Guy's Live release, "The Real Deal" there are some absurdly good jams between Buddy and G. E. Smith, particularly, "Damn Right I Got The Blues" (check out the DVD).
There are various versions, but the best live versions of "Red House" and "Here My Train Coming" by Hendrix are available on some of the unofficial releases after his death. The full version of "Here My Train..." from live at Berkeley is ridiculous.
