Obviously there have been a lot of amazing collabo's in hip hop. What are some of your faves?

Mine:
Mobb Deep ft. Raekwon & Nas - Eye For an Eye
Nas & Mobb Deep- Family
CNN & Nas- Be EZ
Jay-Z & Notorious B.I.G.- Brooklyn's Finest
Eminem & Dr.Dre - Guilty Conscious
Nas, Nature ft. AZ & Foxy Brown- Affirmative Action
Scarface & Nas- In Between Us
Dr.Dre & Snoop Dogg- Still D.R.E.
Ras Kass ft. Dr.Dre & Mack 10- Ghetto Fabulous

...all-time favorite:Nas & AZ- Life's A *****

UGK,Z-RO, Jeezy, Jay-z - get throwed
Z-RO, Bun B, Lil Flip - from the south
Mad *****s............- rollin 25 deep
Jay-z Camron, juelz - welcome to new york city

Albums or songs?

The ones that come to mind are Mos Def and Talib Kweli, Madlib and MF Doom and Dangermouse & Jemini...

Obviously there have been a lot of amazing collabo's in hip hop. What are some of your faves?

Mine:
Mobb Deep ft. Raekwon & Nas - Eye For an Eye
Nas & Mobb Deep- Family
CNN & Nas- Be EZ
Jay-Z & Notorious B.I.G.- Brooklyn's Finest
Eminem & Dr.Dre - Guilty Conscious
Nas, Nature ft. AZ & Foxy Brown- Affirmative Action
Scarface & Nas- In Between Us
Dr.Dre & Snoop Dogg- Still D.R.E.
Ras Kass ft. Dr.Dre & Mack 10- Ghetto Fabulous

...all-time favorite:Nas & AZ- Life's A *****
Your topic...

does this include hip-hop collaborations with artists outside the genre or just rapper w/rapper?

both..anything goes, but it's songs and not albums. Unless there's a hot ass song that is a album collabo.

I'll probably make multiple posts on this topic, but I'll start with these 20:

Notorious B.I.G. & Bone-Thugs-N-Harmony - Notorious Thugs
Trick Trick & Eminem - Welcome to Detroit
Dr. Dre & Eminem - Forgot About Dre
Public Enemy & Anthrax - Bring Tha Noise Remix
Mariah Carey & The LOX - We Belong Together Desert Storm Remix
Mariah Carey & Jermaine Dupri - Sweetheart
Christina Aguilera & Redman - Dirrty
Dr. Dre & Snoop (Doggy) Dogg - Nuthin' But a "G" Thang, Just Dippin', Deep Cover
Del Tha Funkee Homosapien & Dinosaur Jr. - You Played Yourself
Warren G & Nate Dogg - Regulate, I Need a Light
Angie Martinez, Lil' Mo & Sacario - If I Could Go
LL Cool J & LeShaun - Doin' It
LL Cool J & Jade - Loungin' Remix
Jay-Z & Beyonce - Bonnie and Clyde
Too Short, Ant Banks, Mac Mall, Captain Save Em, Rappin' 4-Tay - Players Holiday
Jay-Z & Michael Jackson - You Rock My World Remix
Pras, Mya, Ol Dirty Bastard - Ghetto Supastar
Field Mob & Ciara - So What
Gang Starr & Nice and Smooth - DWYCK
Method Man & Mary J. Blige - You're All I Need Remix

I'll probably make multiple posts on this topic, but I'll start with these 20:

Notorious B.I.G. & Bone-Thugs-N-Harmony - Notorious Thugs
Trick Trick & Eminem - Welcome to Detroit
Dr. Dre & Eminem - Forgot About Dre
Public Enemy & Anthrax - Bring Tha Noise Remix
Mariah Carey & The LOX - We Belong Together Desert Storm Remix
Mariah Carey & Jermaine Dupri - Sweetheart
Christina Aguilera & Redman - Dirrty
Dr. Dre & Snoop (Doggy) Dogg - Nuthin' But a "G" Thang, Just Dippin', Deep Cover
Del Tha Funkee Homosapien & Dinosaur Jr. - You Played Yourself
Warren G & Nate Dogg - Regulate, I Need a Light
Angie Martinez, Lil' Mo & Sacario - If I Could Go
LL Cool J & LeShaun - Doin' It
LL Cool J & Jade - Loungin' Remix
Jay-Z & Beyonce - Bonnie and Clyde
Too Short, Ant Banks, Mac Mall, Captain Save Em, Rappin' 4-Tay - Players Holiday
Jay-Z & Michael Jackson - You Rock My World Remix
Pras, Mya, Ol Dirty Bastard - Ghetto Supastar
Field Mob & Ciara - So What
Gang Starr & Nice and Smooth - DWYCK
Method Man & Mary J. Blige - You're All I Need Remix
Nice list although I don't agree with you on some like Dirrty and that We Belong Together one...

Neils, you heard that 50 is doing a track with Jacko right? Should be interesting...

I'll put another list in a second..

Nice list although I don't agree with you on some like Dirrty and that We Belong Together one...

Neils, you heard that 50 is doing a track with Jacko right? Should be interesting...

I'll put another list in a second..

I'll get another up soon too...

Hadn't heard of the 50/MJ song...

I could actually probably list every song that Mariah's done with another rapper - except for that new one with Snoop - on my list. I'm not embarassed to be a big fan (smilie)

Raekwon ft. Nas- Verbal Intercourse
Busta Rhymes ft. Raekwon- Goldmine
Jay-Z ft. Eminem- Renagade
Jay-Z ft. UGK- Big Pimpin'
Chamillionaire ft. Scarface & Billy Cook- Rain
Scarface Kelly Price- What Can I Do

20 more - hell, I'll probably put up more later...

RUN-DMC & Aerosmith - Walk This Way
Lil Kim, Angie Martinez, Left Eye, Da Brat, Missy Elliot - Not Tonight Remix
Puff Daddy & Mase - Can't Nobody Hold Me Down, Been Around the World
Puff Daddy, Mase, Notorious BIG - Mo' Money Mo Problems
Eminem & Nate Dogg - Til I Collapse
2Pac, Ice Cube & Ice-T - Last Wordz
2Pac & Outlawz - most of the Still I Rise album, Hit 'Em Up
Bumpy Knuckles, John Cena & the trademarc - Flow Easy
RBX, KRS-One, B-Real, Nas - East Coast/West Coast Killas
Dr. Dre & Ice Cube - Natural Born Killaz
Everlast & Kurupt - One, Two
Bone Thugs-N-Harmony & Phil Collins - Home (remake)
Insane Clown Posse & Ol' Dirty Bastard - *****es (hey, it's fun...lol)
Method Man, Redman, Toni Braxton - Part II
Fabolous & Tamia - I'm So Into You
Foxy Brown & Jay-Z - I'll Be
Foxy Brown & Method Man - Ill Na Na
Notorious BIG & Method Man - The What
Master P, C-Murder, Silkk the Shocker - Ghetto D
Shaquille O'Neal & Notorious BIG - Still Can't Stop the Reign

Here's a couple more I remember today:
Slick Rick ft. Nas- Me And Nas Bring it to You Hardest
Scarface ft. 2Pac- Smile
Damian Marley & Nas- Road To Zion

Spice 1 feat Tupac "jealous got me strapped" is some hot **** from back in the day.