The Wu-Tang Clan!!
The mainstream stuff just doesn't make it. More underground artists like Aesop Rock, old Immortal Technique and Jedi Mind Tricks, Killah Priest....stuff like that I'd say would be up there in the top. There's too many mainstream rap songs that have no substance....they're hollow and contain little or no thought. People are tired of hearing about hoes, cars and cash...all that stuff is shallow crap. That's just my two cents.

10
 

Eminem
2Pac
Tech N9ne
T.I.
Ludacris
The Game
DMX
Nelly
Lil' Wayne
Ice Cube

And everyone elses. ;)

I am wasting time and consequently really got into this.
I have been listening to alot more 'underground' recently (i.e. anything post-'99 that isn't bait. Or Kanye West.) so I think I am more qualified to do an all-time top 10. So, if you stripped away any sterling production work these are the MC's I think would look best naked. Lyrically. Or something. Oh yeah g.a.y is bad isn't it? Unless you're Mace.

Of course it all depends on your criteria. Sometimes you want some conscious ****, other times militant Nation rhetoric, slang poetry, abstract nonsense or just classic gangsta (see: Chris Rock's routine on white guys rapping along to NWA). But these guys are pretty consistent in my mind, in order:

1. KRS One
2. MF Doom/Zev Love X
3. Ice Cube
4. Posdnuos & Trugoy (of De La Soul, interchangeable tbh)
5. Rakim
6. Ghostface Killah
7. Q-Tip
8. Mos Def (a bit up his own arse for someone with only one and a half good albums to his name IMO, but they are really good)
9. Slick Rick
10. Chuck D
(10.5. Kool Keith)

Honourable mentions: Raekwon, ODB, GZA, Meth and the rest of the Wu (duh); Notorious B.I.G (I only have 'Ready To Die', but it's insane and I imagine that speaks for the rest of them), Eminem, old Busta Rhymes and Guru. Jay-Z and Kanye are up there, but unfortunately they are both bellends. Yes I am a professional playa-hater.

I've pretty much exhausted my old skool options by now (except for a few I never got into like Tupac), however the list is bound to change the more contemporary stuff I get round to absorbing.

I'm going to have to look into KRS One if you put him above Doom and Ghostface. Very nice list :).

Have you got round to Aesop Rock yet, if not I'm sure he could weasel his way on there.

I have yet to actually, but I am dubious. I have a healthy skepticism of backpacker hip-hop and Aesop is the def jux figurehead... but you are right he deserves at least a download doesn't he?

He does, although he isn't everyone's cup of tea. His voice can be a little annoying.

I haven't really heard the term backpacker hip hop, can you give me an outline?

lol. erm... To me it's hip-hop admired almost exclusively by the alt-rock masses as opposed to hip-hop heads. You know. Students. *crucifix fingers*
I'm on this Aesop ting though, he can't be any worse than Sage Francis. Someone should do a top producers thread...

Heh. I think of it more as a derogatory term used by hip-hop purists against people bringing in any kind of different aesthetic to the music. It's analogous to heavy metal purists who put down anything in metal that draws from something outside the typical set of influences.

oh yeah i agree, it's entirely derogatory. I don't want to come off as an elitist really, but for the most part, that Def Jux sound just comes across as cold and rather detached to me. That's just my personal aesthetic standard.
However I love my shiny new Company Flow album (yes, a Compact Disc *gasp*); it's definitely a grower and I can understand what a landmark it is in hip-hop... but I really have to be in the mood for chin-scratching as opposed to head-nodding (not that the beats aren't great). Maybe the ultra-pretentious stuff will sink it's claws in for good eventually.

As for our friend Aesop, unfortunately I find his voice to be like nails on a chalkboard amplified through 30 8-foot guitar amps feeding back