Thought I'd drop in and give a few recommendations. The last year or so I've been listening to pretty much nothing but hip-hop. The thing that got me hooked was instrumental stuff. It avoids all the lyrical issues that make a lot of hip-hop hard for me to listen to and is some of the more creative music out there. Some of my favorite recent instrumental albums are:
Oh No - Dr. No's Oxperiment and Dr. No's Ethiopium
Oh No is the brother of the more famous Madlib. Each of these albums takes a particular genre of music (italian psychedlic rock for Oxperiment and Ethiopian jazz for Ethiopium) and creates an entire album exclusively from samples from the genre. The results are pretty incredible.
Blockhead - The Music Scene
Really any of his albums are great, but this one from last year is my favorite. He is the producer for a lot of the beats on Aesop Rock's albums.
Blue Sky Black Death - The Evil Jeanius Instrumentals
These are the instrumental tracks to the Jean Grey album Evil Jeanius. These guys make great use of strings in their beats. Imagine John Cale's viola on Venus in Furs over hip hop beats.
For non-instrumental stuff a few of my favorites are:
Serengeti - Get everything. He was basically my gateway back to rap music. I think he's among the best lyricists going in any genre. To start with, everyone should get the albums Dennehy and Conversations With Kenny. They tell the story of Kenny Dennis, a superfan-esque chicago guy who's life goes pretty horribly wrong over the course of two albums. Serengeti's albums with Polyphonic are probably where I'd go next. If you want to try him out for free, you can download some of his stuff for free at audio8.com. He is also giving away a remix album from his group Friday Night at
http://thefridaynight.com/.
Blu & Exile - Below the Heavens
Everyone should hear this. Maybe my favorite hip hop of the 2000s. Exile might be the best producer going right now. Blu has a great lyrical approach on this album, basically rapping about blue collar life.
Deep Puddle Dynamics - The Taste of Rain...Why Kneel
This is basically all the guys from the anticon label recording as a group. It can be a bit pretentious (pretty much par for the course with anticon) but their sound is unlike anyone else. I think of Deep Puddle Dynamics as the bizarro world Wu-Tang Clan.
Also, in addition to the two K'naan albums already talked about here (which are great) he also released a free mixtape project last year called The Messengers. It's K'naan's attempt to highlight the musicians that influenced him. The project was released as three eps, one for Bob Dylan, one for Bob Marley, and one for Fela Kuti. They have since been compiled and released as a single free album at
http://www.jperiod.com/knaan/.
For older stuff that hasn't already been mentioned I really like:
Siah and Yeshua - The Visuals Anthology
Freestyle Fellowship - Innercity Griots