Here's one that's been circulating around the music blogs, courtesy of Unkut.com: A raw, early version of A Tribe Called Quest's "Scenario" featuring a very different arrangement and unheard verses from Dres from Black Sheep and Posdnous from De La Soul. Tantalizingly, Unkut suggests there's yet another unreleased version of the song out there, featuring yet another arrangement and an even better verse from Pos (which is saying something, given how his cameo overshadows everything else in this early version).
In the early '90s these posse cuts were pretty common with the Native Tongues groups�remember how De La Soul worked Phife, Monie Love, Queen Latifah and the Jungle Brothers into a seven-minute, overstuffed remix of "Buddy"�which begs the question of how much unreleased material still exists from these sessions. Even if these sessions never yielded completed songs, it'd be interesting just to hear the raw tapes, especially if the various rappers were toying with different verses.
And while we're on the topic... Since this might be the only chance I get for a long, long time, I might as well take the opportunity to post my favorite Black Sheep video (and, no, it's not this one):