David Gilmour has a great sense of drama in his playing.
Most of my favourite solo's are from Gilmour, probably for this reason. Apart from all the well know Floyd solo's, for me his best guitar playing ever is on the On An Island album. Some real goosebump moments for me there. Comfortably Numb's solo used to be that kind of solo, but I've listened to it too often, and improvised over it too much. As far as "one of those moments" go, the solo's on the Final Cut album are certainly moving - Final Cut and Not Now John stands out.
Jeff Beck, especially on Roger Water's Amused To Death album - magic.
Many of Brian May's solo's are like that too, and sometimes a single riff - not even a solo - way in the background does that to me also.
And I have to agree with Keira - Billy Gibbons has the magic.
I have yet to hear more powerful, emotional and searing guitar work than this track by a Cape Town band called Factory
It's the first time I've heard this, and it's great. Will definitely take the time to listen to their music.