@melonkali,
Coltrane
Miles Davis
Mahavishnu Orchestra
Alan Holdsworth
Bela Fleck and the flecktones
John Zorn; his stuff with Naked City and Masada
Captain Beefheart
Tom Waits
Frank Zappa
Aaron Copland
Arnold Schoenberg- Great ideas
Claude Debussy - Beautiful use of interplay between diatonic and whole tone scales
Franz Liszt - Just a badass
Rachmaninoff - Super Badass
Torche-
YouTube - Torche - Healer
Mastodon
Mind Flayer - interesting primitive style noise rock
Orth Realm - just interesting
Behold the Arctopus- They arguably just complicate their compositions just to complicate them, but they manage to squeeze some interesting stuff in there
King Crimson
Pink Floyd- Not so much without Waters..I especially like Animals
Parliament
Ohio Players Club
Jimi Hendrix
Megadeth-Especially Rust in Peace and Peace Sells
Jimmy Bruno
Django Rhinehardt
Pat Metheny - Not his more recent stuff
Pat Martino
Primus
Colonel Claypool's Big Eyeball in the Sky
Buckethead's Kaleidescalp, Cuckoo Clocks from Hell, Elephant Man's Alarm Clock and a few other interesting songs and albums, but he puts out a lot of junk in between his good stuff
Praxis- another band with Buckethead in it, some of his better stuff I think
Stevie Ray Vaughn
Herbert Hancock
Wes Montgomery
Albert King
Steve Vai- His first couple albums and selected songs from the remainder ( a lot of his stuff is pretty cheesy)
Led Zeppelin
Black Sabbath
High on Fire
Isis-Especially Panopticon; Fantastic composition, awesome example of what you can do with the metal aesthetic when you have actual compositional ability and are willing to experiment
Singer
Russian Circles
Arsis- on occasion
U.S. Maple- really interesting stuff
And many more to come!