
#1: Benzino vs. Eminem
"Back in 2002, Eminem was the biggest-selling, most popular, and lyrically gifted rapper in the world. Benzino was a part-time rapper, part-time magazine boss who didn’t take too well to the barbs Eminem threw (calling him 'Hasbenzino' etc.) following a less-than-perfect 4/5 mic rating for Em's album The Eminem Show in The Source magazine.
Benzino took it to the next logical step: accusing Eminem of succeeding solely thanks to the color of his skin. He staked his entire checkered career on bringing the real-life Eminem show down—along with everyone Shady-affiliated—obsessing through diss songs, radio interviews, and long-form attack pieces in The Source. On the other side, Em effortlessly finished Benzino on two freestyles, and lnterscope pulled all of its advertising from The Source, eventually ending Benzino's reign at the magazine."

Also: #11 - Eminem vs. Triumph The Insult Comic Dog
"In 2002, Eminem walked around like the neighborhood bully in a playground, picking on bystanders whose only mistake was being popular. Moby. Britney Spears. Chris Kirkpatrick—one by one. Eminem chewed them up and spit them out while the public ate it up. He got away totally unscathed until the 2002 VMAs. when he came face to face with a big. bad dog.
More precisely, Triumph the Insult Comic Dog—a dirty-mouthed puppet on the end ofT\/ writer Robert Smigel's arm. AfterTriumph finished ragging on Moby. he barely got off one insult to Eminem before Slim Shady— along with half of D12—aggressively batted the puppet away on live TV. Bad doggy!"
http://www.complex.com/music/2012/01/th ... -rap-beefs