Hear Nas, J Dilla Trade Verses on 'The Sickness'

J Dilla's lost vocal album The Diary arrives on Friday, but first, Mass Appeal has dropped "The Sickness," one of the bonus tracks from the posthumous all-star LP. On the iTunes-only cut, J Dilla and Nas alternate verses over a proggy, warped beat courtesy of Madlib."If I pull a chain out in the sun, it'll blind niggas / First thing that comes to your mind when you think of hardcore," Dilla says on his turn during "The Sickness," with Nas dispatching a lethal, recently recorded verse a