AC/DC were allegedly named after a label on a sewing machine. Riiiiight.note For those who don't know, "AC/DC" is both "Alternating Current / Direct Current" and a slang term for "bisexual".
Area 11: It didn't go unnoticed that the acronym for "GO!! Fighting Action Power" is, well... 'Go FAP'. The band, specifically Sparkles*, didn't even bother using its full name during one of their live performances, meaning it went from Accidental Innuendo to deliberate. There's also the matter that "Fighting Action Power" appears nowhere in the song itself.
Britney Spears: The first line of the chorus of "I Wanna Go," "Shame on me, to need release." She's talking about having a little fun to blow off steam, but "need release" is also a way of saying you need to get laid.
Bryan Adams: Inverted in "Summer of 69." The song title is, in fact, referring to the sexual act, not the year. (Or played straight - Word of God is divided. Bryan says it's deliberate, the co-writer says it was accidental).
BT: This stanza from "The Last Moment of Clarity":
"Tune in the sky Ubiquitous and natural Carry the light And take it deeper and deeper inside."
Carly Rae Jepsen: "Curiosity" delivers the line "don't call me up just so I can please you".
Chicago: Before they even became the Chicago Transit Authority, they went by the name "the Big Thing", which apparently caused some controversy in the Chicago club circuit.
The 1961 song "Quarter to Three" by Gary U.S. Bonds had an exhortation to "blow, Daddy," which was widely snickered over by teenage boys back then.
It's a common joke among Iron Maiden's fan base that "Tailgunner" is an ode to gay sex.
Nail that Fokker, kill that son
Gonna blow ya guts out with my gun
The weather forecasts good for war
Cologne and Frankfurt, have some more
It doesn't help that Bruce got the name of the song from a porno film about anal sex.
Jonathan Coulton realized after writing it that his song "Drinking with You"—a sweet song about, well, going out drinking with someone you have UST with—could be construed as being about date rape. He put a comment in the song's info on his website how he'd realized the undertones, but that was assuredly not his intent and the song's sweet tone was meant to be sincere.
Joy Electric: From "Monosynth"'s chorus: "With a stroke of magic hands, I'll make your dreams come true..."
The Kidz Bop rendition of Cascada's "Evacuate the Dancefloor" replaces "Can't stop 'cause it feels like an overdose" with "Can't stop 'cause it feels like it's getting close".
The Magnetic Fields: 69 Love Songs was apparently chosen because of its appeal as a cover design.
The Marshall Tucker Band's "Long Hard Ride" is definitely about a horse.
The Megas: Probably unintentional, but Woodman is the master of machines... and of the birds and the bees?
Nine Inch Nails in "Ruiner": "How did you get so big? How did you get so strong? How did it get so hard? How did it get so long?"
Also, the song "Vessel" opens with "I let you put it in my mouth/I let it get under my skin".
*NSYNC: "Up Against the Wall" was written by Justin and JC and notably used the popular slang term "shorty". Some fans jokingly called the song Justin and JC's love ode to Chris, as Shorty was the group's oft used nickname for him.
Rascal Flatts has a song called "Bob That Head". Not surprisingly, this song has been the subject of derision, mainly in the form of fellatio jokes.
REM once did a song inspired by the "last call return" feature on phones. However, given that the song's title contained both an Unusual Euphemism they had used before ("Star", also used by the Rolling Stones), while the other was a euphemism for a particular sexual act "69", some people no doubt wondered why the title had nothing to do with the act...
Shiv-r: From “Hollow Mask”: “Every day I lose myself/I wish I could believe/that I’m really somebody else/when I’m down on my knees”. Wait, what?
The songs "See Me, Feel Me" and "Sensation" from Tommy.
And this exchange between Beenie Man and Bounty Killer, in an argument about Beenie's gaining inspiration for his musical drive from Bounty:
Beenie Man: Bounty Killer, Bounty Killer! Mi love you, Bounty Killer!
Bounty Killer: You can't love me - I'm a male!
Beenie Man: Nuh dem way deh, Bounty Killer—
Bounty Killer: I'm a male! Go and e-mail some f—-ing female!
The Who: Pete Townshend has said that "Squeeze Box" is about nothing more than a woman who plays accordion to the annoyance of her family. But John Entwistle said that when he first heard the song, he knew "it was about tits." According to this, however, "[Squeeze Box was] Intended as a poorly aimed dirty joke."
"Stay the Night" by Zedd and Hayley Williams contains the line "come pour yourself all over me", which is supposed to be connected to the previous lyric "I am fire, you're gasoline", but it can come off as something much messier
The song "Happy Sensations", popularized in the Ape Escape series of video games, can be interpreted as such. (Just look at the title!) Lyrics include "my heart is pounding", "I'm jumping in", "loving this feeling", and to make things worse, at times you can hear a cartoony "boing" sound effect in the background (remind you of anything?)
The Christian hymns "He Touched Me" and "Let Me Touch Him".
"Pack Up Your Troubles" has a couple of instances of accidental innuendo. One of the lyrics is, "While you've a lucifer to light your fag, smile boys, that's the style...". In modern-day America, "fag" has completely different connotations to what the song means ('fag' meaning 'cigarette'). Also, if your head is far enough in the gutter, "Private Perks", especially out of context, can have some connotations that could fit under this trope, or double entendre.
"We can dance if we want to, we can leave your friends behind"