I've always been impressed by lead guitar breaks, especially when the solo becomes the propelling accent that drives the song along. I've not prepared a top ten, but very high up there would be George Harrison's solo on I've got my mind set on you wher he actually plays only three bent notes. George was a master of minimalism. Larry Carlton's Kid Charlamagne is another classic that took the song to another level.
My all time favourite though is Robben Ford, twelve bar punch in solo on this somewhat obscure track, Don't Let Me Down, by Michael Macdonald.
So imagine you are playing the guitar. It's a session AFAIK and you're brought in to do a twelve bar solo. How much energy can you raise? There is no harmonic movement and unusually the song is in 6/4 time, probably unfamiliar rythmycally. Well Robben pulled out a textbook tour de force solo. It has a beginning, a middle and an end, builds dynamically, has tension, passion and power. When I first heard this solo I listened to it again and again worshipping at the Robben Ford altar.
OK you could argue there are more technical, faster, or more harmonically ingenious solos out there, but for me this represents a really economical, creative and powerful solo for what was probably a Friday afternoon session. If I were the producer I would have been tickled pink. Enjoy! (If you're impatient the solo starts at 2:27)