Don't like CoB much, but I think Everytime I Die's solo, while being far away from being the best solo of all time, deserves to be mentioned in this thread.
I might get bashed for this but I think the solo in Fundementally Loathsome by Marilyn Manson should be mentioned as well. It was written by Zim Zum and performed by Twiggy Ramirez. It is so sad and yet so powerful. If you have yet to hear this song give it a listen.
Pink Floyd - Comfortably Numb
Metallica - One
Opeth - Leper Affinity
Dragonforce - Fury of the Storm. seriously, listen to it before you bash me. It's tasteful and makes a change from their usual wankery.