doglooseOne of the factors that led to Jason Newsted's departure from Metallica in January 2001 was frontman James Hetfield's reluctance to allow his bass player to indulge in...

One of the factors that led to Jason Newsted's departure from Metallica in January 2001 was frontman James Hetfield's reluctance to allow his bass player to indulge in side projects during the band's downtime.

While it's true that the Metallica frontman has never officially joined any other band (Spastik Children notwithstanding), Papa Het has done his share of guest appearances over the years, usually either helping out a friend or paying tribute to a fallen hero. Though rare they may be, we managed to pull together 10 of them, including live and studio cuts, in this convenient playlist.

As for Hetfield's main band, head here[1] for our ranking of the 100 greatest Metallica songs of all time.

"Stone Cold Crazy"
Queen with James Hetfield, Tony Iommi
In 1992, an all-star cast of musicians gathered at London's Wembley Arena for the Freddie Mercury Tribute Concert for AIDS Awareness. Two years earlier, Metallica had covered the Queen classic "Stone Cold Crazy" for the Rubáiyát: Elektra's 40th Anniversary compilation, so James Hetfield seemed the perfect fit to join the surviving members of Queen—not to mention Black Sabbath guitarist Tony Iommi—for the Sheer Heart Attack cut.

"Man or Ash"
Corrosion of Conformity
James Hetfield may not be credited for his backing-vocal performance on Corrosion of Conformity's 1996 album Wiseblood, but there's no mistaking his signature growl on the album cut "Man or Ash." CoC frontman Pepper Keenan would later repay the favor, singing a verse on Metallica's cover of Lynyrd Skynyrd's "Tuesday's Gone" on their 1998 covers compilation, Garage, Inc. Thanks, Pep!

"Would?"
Alice In Chains featuring James Hetfield
There's an infamous incident (that can be found on YouTube) featuring the members of Metallica mocking Layne Staley's heroin addiction after Alice In Chains

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