My favorite Boston song. Not sure about a 10 Min live version but the studio version is 7.5 Min
FYI - The main force behind Boston is Tom Scholz - an MIT Engineer - he made is own recording studio and many of his own instruments (mainly paddles to give the guitar the unique sounds)
Two/three of my favorites (there are many more -- including a few already represented -- so many great songs in this thread already):
Reeling in the Years (Steely Dan):
Eruption/You Really Got Me (Van Halen ... yah I know, technically two separate songs, but the first is almost always played in tandem with the second, so feels like an intro to me):
And for brass aficionados, there's this (plus one monster guitar riff embedded in the middle) -- the instrumental tour de force that is 25 or 6 to 4 (Chicago):
What is, is.
What was, will be.
What will be WAS, but will be again.