Two that come to mind, off-hand, are both from Santana.
1) She's not there, with the classic psyched out guitar solo at the end ("end", its almost 1/2 the song!).
2) Changes. That entire song stands on the shoulders of Carlos's two guitar solos and he never sounded better.
I always loved the ending of Shapes of Things by The Yardbirds. It ends with mostly the guitar but some of everyone playing a kind of faux echo of fading eighth notes.
Not to veer from the outro premise but this song has amazing changes like from the heavy quarter note downbeat verses to the release of the open backbeat chorus and the sixteenth notes behind the guitar solo. Not to mention the little high hat flourish pick-ups out of the breaks!
These guys deserved more credit than they garnered!