The Greatest solo in guitar EVER played.

I really dig Sweet Child O'Mine's solo at the moment.
And another one I love is Since I've been Loving You by Led Zeppelin, even more so the Live version at Madison Square Garden, the sound is sooo sweet.
Then there is X Japan's Voiceless Screaming, a beautiful acoustic song, although nobody will know the band.

And at last there is a guy named House The Grate, who did a great remix of a Vdeogame track, please do me the favour and listen to it, it's an amazing work...

http://www.housethegrate.com/music/housethegrate_-_La_Hora_es_Tarde.mp3