the reason eyedea and slug collab alot is because their on the same Label...Rhymesayers Entertainment....(i believe it's slug's label)....

it also is the home to
Brother Ali
Mf Doom
Felt
Blueprint...

dope label

But my fav. emcees from the underground are
Chino XL
Copywrite
Cage
Atmosphere
Scram Jones
Crooked I
Canibus
Brother Ali
and thats all i can think of right now...i'll hit yall back up with some more dope emcees to check out