I no longer pay too much attention to guitar solos, because frankly very few and far in between are actually memorable. Most sound the same to me, and many are way longer than what I'd like them to be.
But one that gets me every time (despite the actual duration of the solo, which is a lot) is the solo in Comfortably Numb. There is something about the phrasing, the feel, and even the effects used that make me shiver.
Others would be many Jimi Hendrix solos, especially those where he doesn't go completely nuts and sexually explicit (with all due respect to the honourably departed Jimi... I actually admire how much passion he had for his music).
Some solos by Angus Young also get to me... only because of the sheer power he delivers with many of them. Plenty of his stuff is kinda derivative, though. But what he does, he does it great.