The lead guitarist for the timeless Pink Floyd is one of the most underrated guitarists there is. While he has the obvious talent to be considered amongst the Pages, Claptons, and Richards of the world, his relatively shy nature keeps him for the public spotlight.
Behind Blackmore, I find Gilmour the greatest guitarist of the last 40 years. His musical style covers blues progression, through jazz, rock, metal and even slide guitar. Further to this, he also plays keyboards and bass very well and has done on Pink Floyd albums.

Considered a 'slow hand' Gilmour uses techniques such as bending and sustain to great effect, and has had three solos listed in the top 100 -
Money, Time and of course
Comfortably Numb (which he actually wrote for his solo album but it ended up on
The Wall when he thought he already had enough material! Would it have been as big??).
I cried when Pink Floyd reunited at Live 8 a few years back, and it seemed that maybe the impossible could come back - Floyd making a new album, however this time is was Gilmour (instead of the normally morose Waters) who squashed all chances. Either way, the death of Rick Wright (so soon after Syd Barrett) put pay to any chances of a reunion. Ah well, we still have the music!