Jeru the Damaga is great.
My all time favourite rapper would have to be Immortal Technique, simply because he's clever as hell and, unlike all rappers signed by large record companies, gets to say what he wants. Revolutionary Vol 1. and 2. were incredible albums. Didn't get to hear 3rd World yet.
Very heavy song, but it's the first one I've heard from him and it's awesome. Not as politically charged as most of his work, but it's still great and indicative of his style:
[youtube]http://www.youtube.com/watch?v=f7JYrt1eG_Y
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