Jurassic 5
Del the Funkee Homosapien/Pretty much anything by Hieroglyphics
Mos Def
Talib Kweli
A Tribe Called Quest
Outkast, their older stuff anyway.
Of course, the oldschool stuff. Run DMC, Grandmaster Flash, etc. I used to listen to rap a lot more, but I pretty much stopped. Now I listen to girly eurodance all day. But these are a few songs I remember off the top of my head. If you like gangsta rap, Tupac was always my favorite for gangsta rap, but I hate gangsta rap now, much too negative of a music style.
[youtube]http://www.youtube.com/watch?v=rsLMHc6G5rU[/youtube]
[youtube]http://www.youtube.com/watch?v=4CLQet7gwjw[/youtube]
[youtube]http://www.youtube.com/watch?v=-oCXwl7XBiQ[/youtube]
As far as R&B goes, I LOVE R&B, but I pretty much only listen to older R&B. Pretty much the only newer R&B I've heard and liked is Maxwell and Sade. The best R&B era for me was the 80s. LOTS of R&B I can post.
[youtube]http://www.youtube.com/watch?v=wbL2lMn34Oo[/youtube]
"Oh Sheila" is like my favorite song ever. Well not quite, but it's up there. I've had this on repeat for like a day before, it's great.
[youtube]http://www.youtube.com/watch?v=HgM3BWp42vc[/youtube]
[youtube]http://www.youtube.com/watch?v=tVe0x8jIfdQ[/youtube]
This is Japanese jazz fusion, but it's funky as all hell. Toshiki Kadomatsu. Jazz fusion is a wonderful genre to look into, super funky. Another jazz fusion artist I like is Shakatak.
[youtube]http://www.youtube.com/watch?v=w6DQavhJUrk[/youtube]
Sade's been around since the late 80s I believe, but they're one group that's actually improved with age. It's slower music, though.
I can post a LOT more stuff, so PM me if you wish for more music. I can even upload some for you if you want.