theshityoulearn
Holy hell, the shit you learn on Wikipedia!
"Mah Nà Mah Nà" debuted as part of Umiliani's soundtrack for the Italian softcore pornography movie Svezia, Inferno e Paradiso (Sweden, Heaven and Hell) (1968), a pseudo-documentary film about wild sexual activity and other behavior in Sweden ("Mah Nà Mah Nà" accompanied a scene set in a sauna). A soundtrack album, "Svezia, Inferno e Paradiso" was released in 1968. The movie was also released under the English title Sweden Heaven and Hell.- From this Wikipedia article
Uhm... so one of the most popular Muppets songs of all time... started in a softcore porn. Crazy eh?
Edit: Found the video (NSFW 18+). Thank you interwebs! Keep replacing my childhood memories with nakedness. It won't scar me as bad as kids nowadays seeing Daniel Radcliffe's four-pack abs.
Oh yeah, needless to say, not safe for work. I mean, okay, it's 60s softcore porn, it's nothing, really, a little bit of toplessness, but you might have an uptight boss. Don't say I didn't warn you.