Update 15

What's up fam!

Heavy bass, sick wordplay, awesome track!
J Dilla - Jungle Love (Feat MED & Guilty Simpson)
'If I was hotter, I'd drink straight vodka, 
Spit out flames and piss lava'.

Hardcore underground hip-hop track, the beat makes you go ape shit! Ill AOTP track if you ask me!
AOTP - Godzilla (Celph Titled, Jus Allah, Apathy, Planetary, King Magnetic & Vinnie Paz)

Vinnie Paz, founding member of Jedi Mind Tricks and Army of the Pharaohs, I personally like his tracks alot. This year he released a solo album, Season of the Assassin:
Vinnie Paz - End of Days
Vinnie Paz - Same Story (My dedication)

Giant Panda, I don't know alot of tracks by them but the tracks I've heard always are great!
Giant Panda - T.K.O.
Giant Panda - The 90's

Mos Def, not much has to be said, guaranteed fire anyways.
Mos Def - Speed Law