While RUN DMC and Erik B were without a doubt hip-hop pioneers, for my money Slick Rick and Special Ed were the most amazing 20th Century rappers.
All I have to hear is the first couple seconds of "A Children's Story" and I'm already bobbing my head. As for Special Ed, in "I got it made" he claims that "when my dishes got dirty, I got Cascade" and goes on much further down the verse to rhyme this with "they [those who would seek to approach him with malice aforethough] couldnt harm me <pause> I have an army brigade." This is punctuated in the video by the representation of said ruffian fleeing from about 3 other guys... one one whom is holding a rolled up newspaper.
Ah, someone beat me to PE. And no love for Doug E. Fresh?
And on Saturdays from noon to 3:00, check out the streaming audio at wmse.org because they do the "Saturday Afternoon Boogie Bang" show, which is 3 hours of old school stuff like this, with some old funk and R&B thrown in.