Yasiin Bey, formerly known as Mos Def, has lately been releasing a series of freestyles that he's called Top 40 Underdog, in which he goes in over radio-big rap songs. The first one was "Niggas In Poorest," and the latest, called "Bey," uses the instrumental from Lil Wayne's "John" and pays tribute to Biggie Smalls, who would've turned 40 today ...