Metallica's "One" always blows me away. And that bridge to get to the solo sounds awesome backwards.
Some favorites of mine.
The opening riff is classic but the solo at 2:19 is the most incredible sound ever....such high-pitched notes that strain credulity, it sounds literally like the guitar is wailing and mourning.
The solo at 3:13 is one of my all-time favorites, and I love the version performed live on SNL just as much as this one.... I wish I could find the video on Youtube because it is excellent. I purchased the sheet music for this song to see the solo in musical notation, because it is so gorgeous.
I'm a Yardbirds nut, so I gotta include a few of these. Jeff Beck's piece at 1:41, which starts with siren sounds and then delves into a blistering solo, is awesome.
Jimmy Page's solo at 1:35, Eastern-influenced, makes one wish it lasted a few seconds longer before the fade-out.
Page's solo at 1:31 is the archetype of the "Dazed and Confused" solo, and stands on its own as a great solo.
Hard to pick just one from Led Zeppelin, but this is sublime.
This song takes me back to my childhood.....ahhh the memories. Technically not a guitar solo, but the electric sitar solo is fantastic and it ends with an innovative pitch-shifting organ solo.
One of the best rock songs ever, loaded with many great solos...the last one however is my favorite....the plucked notes sound like seagulls.