Sure, it was a private holiday concert thrown by the corporate entity Eldridge Industries last night. But it attracted a ton of real star power. At Garcia's, a 250-person space inside the Capitol Theatre in Port Chester, NY, the house band for the evening was Slash and Duff McKagan from Guns 'N Roses, Chad Smith from Red Hot Chili Peppers, and producer Andrew Watt. They're known as The Dirty Bats. No big deal there, a money gig is a money gig. But the revolving cast of frontpeople for the show was kind of earth-shaking.

Yungblud kicked things off with the band running through the Rolling Stones' "Start Me Up". the Faces' "Stay With Me", and just like at the VMAs, Black Sabbath's "War Pigs". Brandi Carlile did Led Zeppelin's "Black Dog" and Queen's "Tie Your Mother Down", along with her own song "The Story". Then Anthony Kiedis joined the ensemble to sing five different classics from five very different strains of classic rock: Motörhead's "Ace of Spades", Iggy and the Stooges' "Search and Destroy", Black Flag's "Nervous Breakdown", Sly and the Family Stone's "If You Want Me to Stay", and perhaps most surprisingly since it's outside of his punk-funk pedigree, the Allman Brothers Band's "Whipping Post".

As you can see, bigger and bigger names kept joining up for this all-star live-band karaoke, and next was stadium-filler Eddie Vedder, probably the most surprising name to see on this type of gig. He sang Pearl Jam's "Better Man", "Corduroy", and "Wishlist" — the three one would expect if he's not holding a ukulele — along with the Dead Boys' punk classic "Sonic Reducer", the Stones' "Waiting on a Friend", and Elvis Costello's "(What's So Funny 'Bout) Peace, Love, and Understanding".

Finally, Bruno Mars came out to sing an even wider-ranging lot than Kiedis: Led Zeppelin's "Whole Lotta Love", the Police's "Roxanne", Jimi Hendrix's "Fire", Michael Jackson's "Dirty Diana", and, finally, Nirvana's "Smells Like Teen Spirit". which he'd never done in full before, only as a mash-up with MJ's "Billie Jean" a couple times.

The big group singalong at the end according to Last.fm was Chuck Berry's "Johnny B. Goode" and Neil Young's "Rockin' in the Free World". Not gonna lie, this probably ruled. Check out some footage from this pop-up Rock and Roll Hall of Fame ceremony-for-hire below.

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