IMHO, the best guitar player is Eddie Van Halen. I didn't realize how amazing the guy was until the younger generation guitar players in most bands stopped playing.

I know that there several other great ones out there but for some reason this guy is my favorite.

http://www.youtube.com/watch?v=ZQxDW_-pz1o&feature=related

Jimi Hendrix and Eric Clapton come to mind. However, my all-time favorite is Carlos Santana. Another notable is B.B. King.

8-)

Brad Pasiely is THE BEST I've ever heard. That boy can PLAY!

Wow. Tough to pick one all time best so I'll go with 5 in no particular order.

Jimi Hendrix

Eddie Van Halen

Pat Metheny

Al DiMeola

SRV

After looking at my list I'd have to say it's a close tie between Jimi and SRV as the best ever. A lot of guys have the technical ability but imo not many guys out there have/had as much natural ability and soul that these two had. When you watch these guys play it's like the guitar is just an extension of their body, like playing the way they did is just an instinctive thing they were born with.

Also gotta five honorable mention to my man Trey Anastasio. Saw Phish many many times and haven't seen him solo as much as I'd like. He can flat out play.

SRV did Jimi better than Jimi did Jimi.  Make sense?

SRV gets my vote.  

He once said that he is not playing the guitar,  it is playing him.  If you've seen him play,  you'll get it.

Frank Zappa also gets a nod.

Joe Pass, Charlie Christian,Herb Ellis,Barney Kessler,Jimi Hendrix,SRV,BB KING,Albert Collins,Steve Cropper,Frank Zappa

Django Rheinhardt,Glen Cambell and Earl King

Eddie Van Halen doesnt even exist in the same universe as these guys!

The best ?

There 's no such thing as the best guitar player because there 's so much talent out there

Let 's see:

Jimi Hendrix

Eric Clapton

Eddie Van Halen

Randy Rhodes

Ritchie Blackmore

Jimmy Page

Phil Collen

Aldo Nova

Michael Schenker

How 'bout a chick ? Lita Ford

SRV did Jimi better than Jimi did Jimi. Make sense?

SRV gets my vote.

He once said that he is not playing the guitar, it is playing him. If you've seen him play, you'll get it.

Frank Zappa also gets a nod.

I had the privilage of listening to a group of musicans talking with  SVR at Tipatina's in New Orleans  . A guitar Player made the statement to him ," You do Jimi , better than Jimi" Steves response was" Yea but I am not as good as Jimi, I play his songs, BUT HE WROTE THEM" Steves humility was incredible.

Hey Raul You are right a female belongs on the list

BONNIE RAITT

Stevie Ray Vaughn and Clapton are awesome.

"Dimebag" Darrell Abbott is my favorite

John Petrucci and Joe Satriani

The best ?

There 's no such thing as the best guitar player because there 's so much talent out there

Let 's see:

Jimi Hendrix

Eric Clapton

Eddie Van Halen

Randy Rhodes

Ritchie Blackmore

Jimmy Page

Phil Collen

Aldo Nova

Michael Schenker

How 'bout a chick ? Lita Ford

Lita Ford rocked in the 80's, I saw her in Concert in 1988, I was 15. At the time I was into metal scene big time, and Lita was a rock goddess.

Some other great guitar palyers are:

Joe Santriani

Mark Knopler of Dire Straits

And on the country side Vince Gill and Roy Clark.

In no particular order.

Eric Clapton

Jimmy Page

SRV

Jimmi Hendrix

BB King

Eddie Van Halen

Kirk Hammet

Steve Vai

Robert Johnson

Carlos Santana

Frank Zappa

James Taylor

Randy Rhodes

Slash

Tom Morello

Zakk Wylde

Female guitarist - Ani DiFranco

I would add  

Alvin Lee of Ten Years After

Billy Gibbons of ZZ Top

Howard Duane Allman of Allman Brothers Blues Band

What? No mention of Chet Atkins??)  I'd vote for BB King. I've always liked listening to him play the blues and I hear from others who have been fortunate enough to meet him in person that he is a real down to earth gentleman.

Antonio Banderas as "El Mariachi"

for real though, gotta go with Jimi.

Eddie Van Halen

Slash

Randy Rhodes

Zak Wylde

Jimi Hendrix

Kirk Hammet

Jeff Hanneman of Slayer

Richard "Scholle" Kruspe of Rammstein

Tony Iommi of Black Sabbath

Oh yea add 1 more that many people don't like but I do Ted Nugent Stranglehold  

Those rock and roll pickers couldn't carry Jerry Reed's or Chet Atkins' thumbpicks.

Geez, there are so many and it is difficult to compare between styles.  I agree with many mentioned so far.  Here's some repeats and some that haven't been mentioned.

Andres Segovia - One of the great classical guitarists.  

Christopher Parkening - Another great classical guitarist.

Paco De Lucia - Flamenco, extraordinary

Wes Montgomery - Jazz Pioneer

Steve Vai - Hired to play impossible guitar parts by Frank Zappa

John Petrucci - Dream Theater wizard

Jimi Hendrix -  a pioneer

Eddie Van Halen - Another pioneer.  

Randy Rhodes

Al Di Meola - fusion

Stevie Ray Vaughn

Paul Gilbert

There are so many more but these lists can go on and on.  

Jimi Hendrix

Eddie VanHalen

Jimmy Page

Santana

SRV

BB King

No real order and will think of several after I post this. Thanks Catt for mentioning

Alvin Lee

Joe Walsh

Eric Clapton

Eddie Van Halen

Jimi Hendrix

Stevei Ray

Slash

Jimi Page

Too long a list for me, and thay've all been mentioned already except for Steve Morse

Consider, Jose Feliciano.