It seems like when a duet is sung, in pop music, it’s almost always between a man and a woman. The contrast of high and low voices has led to this being the norm, I guess, plus the fact that most duets tend to be romantic love songs. Besides that song between Peter Cetera and Terry Kath by Chicago (can’t remember what it’s called,) are there any other male-male duets?
David Bowie and Bing Crosby singing “Little Drummer Boy” on Bing’s Christmas special. Their performance is cool on many levels.
You misspelled “oh-so-wrong”… 
For that matter, David Bowie and Mick Jagger (snerk) on the late-80s remake of “Dancin’ in the Streets”.
Jimmy Buffet and Frank Sinatra did the best version of Mack the Knife out there.
Better than Bobby Darin?
Frank did a bunch of duets with rock stars like Bono in the early 1990s. His voice was gone by then.
My fantasy duet would be Donald Fagin of Steely Dan with a young, high-voiced singer like Jason Lytle of Grandaddy. Not sure what song they would do, but that contrast of voices would be amazing.
That’s the beauty of it! It’s the only Christmas video I like because of the “WTF?” factor, and it’s not a bad song to boot.
Are we including musical theatre? If so, I’ll throw in Agony from Into the Woods, just to start.
There’s this Montreal band that’s bouncing around the indie scene now called The Unicorns. On their album “Who Will Cut Our Hair When We’re Gone”, they have several male duets that are kind of tongue-in-cheek. One of the catchier ones is “I Was Born A Unicorn” which has a hilarious back-and-forth between their two lead singers.
Julio Iglesias and Willie Nelson did “To All the Girls I’ve Loved Before”.
“Ebony and Ivory” Paul McCartney and Stevie Wonder
“The Girl is Mine” McCartney and Michael Jackson
And there aren’t many female duets either, the only one I can think of is Barbra Streisand and Donna Summers “No More Tears.”
1994, this one. I’ve always preferred his older voice. Less range, less power, but a lot more control. You heard Angel Eyes on the 80th birthday album?
I saw a version of Little Drummer Boy with Clay freaking Aiken greenscreened and mixed with Bing. That moment I swore off American Idol. Forever.
Cream’s “Sunshine of Your Love” alternates lines sung by Jack Bruce and Eric Clapton.
Elvis Costello’s “From a Whisper to a Scream” is a nifty duet with Glenn Tillbrook.
Philip Bailey and Phil Collins had a hit with Easy Lover.
Micheal Jackson and Stevie Wonder did Just Good Friends and another song I can’t remember.
I really shouldn’t find that so amusing (if only for Stevie’s sake) considering the recent…unpleasantness…
I thought the OP asked for MALE duets. One could reasonably argue against this pairing.
And one could reasonably argue that making one more “Michael Jackson is effiminate” joke is so far beneath the standards of this board that the person making it ought to resign in shame right now. But I digress.
Don’t Go Breakin’ My Heart by Elton John and Ru Paul.
Willy Nelson and Toby Keith - Beer for my Horses
Jackson & McCartney (boofuu’s protest notwithstanding) later had another duet, “Say Say Say”.
David Bowie also turns up in “Under Pressure” with Queen (with Freddie Mercury, of course…that counts, doesn’t it?).
There’s also “Don’t Fight It” with Kenny Loggins and Steve Perry (of Journey).
I just have to also include the cover of the Scorpions’ “Blackout” by Six Feet Under with John Bush (of Anthrax).
D
I think I love you, Otto.
As for the OP, Ozzy has done songs with Lemmy Kilmister, Alice Cooper, Frank Zappa, and Peter Steele.