As a life-long audiophile, I've always found it fascinating to read and watch stories behind the music - especially in regards to the production and studio work that goes into the songs we hear.  I recently discovered this gem online via a production forum that I read on a regular basis.

The video shows Beatles producer George Martin - along with his son Giles (who is now in charge of the studio recordings made by the Beatles) - as they "play" with the mix of Here Comes The Sun from the master source tape.  By soloing out a different track or two, they discover a long-lost George Harrison solo that didn't make the final mix of the song.  It appears that even George Martin forgot that it existed.