I’ll say this for Brian May — the man is not afraid to venture outside of his comfort zone when choosing his non-Queen collaborations. Tracking them all down was no easy task, mind you. Many of the albums he appeared on are out of print, which may not say much for their popularity but should not be viewed as an indictment against their quality. Mostly.

“Diggin’ My Potatoes” by Lonnie Donegan (from Puttin’ On the Style, 1978) — This is the first instance I can find of May playing without Queen on another artist’s album, and this one makes perfect sense. Donegan, England’s King of Skiffle, had an incalculable influence on an entire generation of British musicians. The star power on this record is formidable indeed; this track features May on guitar and Elton John on piano.

“Stay With Me Tonight” by Jeffrey Osborne (from Stay With Me Tonight, 1983) — The only way you would even know Brian May played on this otherwise pleasant hunk of pop funk is the brief guitar solo. For Queen fans who think the band went off the deep end with Hot Space, just imagine what might have been with this track added.

“A Time for Heroes” by Meat Loaf (from A Time for Heroes, 1987) — Pretty standard mid-’80s stadium rock, with a twist. This song was the official theme for the 1987 International Summer Special Olympics World Games. There was an instrumental version released as well, and it was performed by Tangerine Dream of all acts.

“Love Lies Bleeding (She Was a Wicked, Wily Waitress)” by The Cross (from Shove It, 1988) — The Cross was Roger Taylor’s solo project in the ’80s, formed after Queen’s supporting tour for A Kind of Magic ended. Freddie Mercury has a guest spot, as does May. This is about what you would expect from a Roger Taylor solo song, which is to say that May’s guitar is the best part of it.

“When Death Calls” by Black Sabbath (from Headless Cross, 1989) — This is a damn fine tune from an era many Sabbath fans have forgotten about. It’s especially notable in that this is the only time a guitarist other than Tony Iommi has played a solo on a Black Sabbath record. I really like how he kept enough of his signature style so you know it’s him, but really played just what the song called for.

“New Damage” by Soundgarden (from Alternative NRG, 1994) — Soundgarden recorded a kickass new version of the closing song from 1991’s Badmotorfinger for a Greenpeace album touting solar energy, and May’s guitar was overdubbed on it. So yeah, Soundgarden and Brian May. It’s about as face-melting as you’d expect. And carbon neutral to boot!

“Bad for Good” by Meat Loaf (from Bat Out of Hell III: The Monster Is Loose, 2006) — Mmm, a second helping of Meat Loaf! I never really got the appeal of the guy, but damn he’s just so earnest. Oddly enough, this is probably the most Queen-like of May’s guest appearances. That wall of overdubbed guitars is unmistakable.

“Defying Gravity” by Kerry Ellis (from Anthems, 2010) — Well here’s an unexpected turn. Ellis is an English stage actress/singer who played Elphaba in the London production of Wicked before making the move to Broadway in 2008. In 2010 she released an album, Anthems, that was produced by May and features a mix of Wicked songs and original numbers. “Defying Gravity,” one of the numbers from Wicked, kicks off with that unmistakable May sound. It’s not totally my cup of tea but there’s no denying the strong arrangement and Ellis’ pipes, which are quite good.