clocking in

For Eminem, it's a 9-to-5 job.

Assuming the recording work would begin in the evening—as it usually does in the music industry—the singer Akon arrived at the studio around six p.m. to begin his first collaboration session with Eminem.

"Em just left," the studio guys told him. Akon called the rapper to find out where he'd gone. As it turned out, Eminem had gone home. It was the end of his workday.

"You coming back?" Akon said. "I just got here."

"Yeah," Eminem replied, "I'll be back there at nine a.m."

The next day, Akon and Eminem both arrived at the studio at nine a.m. and got to work. At one o'clock, Eminem went to lunch for an hour. At five, the rapper took off his headphones mid-verse.

"He's halfway in, he's like, alright bro, I'll see you tomorrow," Akon recalled.

Work on the track proceeded along these lines. Eventually, it culminated in a hit track, "Smack That."

Producer and Def Jam co-founder Rick Rubin recently talked about working with Eminem, too.

"He's always writing in a book," Rubin said. When he wasn't rapping, Eminem would fill one notebook after another. "Are these rhymes to use?" Rubin asked him.

"99 percent of what I write I'll never use," Eminem replied. "It's just to stay engaged in the process of writing and finding new ways to write so that, when I need it, it just comes."