"Once in a Lifetime" (Talking Heads)

The gestation of Remain in Light (1980) by Talking Heads pretty much can be traced to three events.
First, early on in his relationship with the band, producer Brian Eno played them a copy of Nigerian artist Fela Kuti's Afrodisiac (1973)--a prototypical example of Afrobeat (a genre that Kuti himself created, which combines traditional African folk music with funk and jazz.)
Second, back when hip-hop was brand new, Talking Heads drummer Chris Frantz gave frontman David Byrne a copy of Kurtis Blow's "The Breaks."
Third, during the band's brief hiatus in 1979, Byrne and Eno collaborated on an experimental project called My Life in the Bush of Ghosts (released in 1981), which relied heavily on creating funk-influenced tracks around "found sounds"--including everything from snippets of static to recordings of radio evangelists.  (It's considered the first commercial example of modern sampling and largely established the precedent for sample clearance practices.)
Each of these events influenced the way the band tackled the creation of Remain in Light.  Instead of taking their usual approach of writing new music, rehearsing and arranging those songs, and ultimately putting the polished material on tape in the studio, they instead reversed the process: jamming in the studio, listening back at what they'd spontaneously created, culling the parts they liked best, and then writing lyrics and other melodies around those grooves.  Essentially, they were "sampling" their own rhythms, basslines, guitar licks, etc.--the end result being funky, trance-like songs that had the rhythmic complexity of Afrobeat.
When it came to putting words to the music, Byrne took cues from his "found sounds" and nascent hip-hop, harvesting direct quotes from sources like Nixon's Watergate Tapes as well as coming up with stream of consciousness chants and hooks that paid homage to Kurtis Blow and The Sugarhill Gang.
Specifically, "Once in a Lifetime" developed out of a jam session and Byrne's recordings of Pentecostal preachers, hence his very proclamatory, sermon-like delivery.  And despite what many critics thought, Byrne wasn't railing against 80s excesses in the song; he was just pondering how we often go from "point A" to "point B" without thinking.  As he stated in a 2012 NPR interview, "We operate half awake or on autopilot and end up, whatever, with a house and family and job and everything else, and we haven't really stopped to ask ourselves, 'How did I get here?'"
And that indelible chorus?  After Byrne hit a brick wall, trying to come up with some sort of melody that fit the groove, Eno came up with something off the top of his head, using nonsense syllables initially.  In time, it developed into the lines we all know:
Letting the days go by, let the water hold me down
Letting the days go by, water flowing underground
Into the blue again, after the money's gone
Once in a lifetime, water flowing underground...

 

"Crosseyed and Painless" (Talking Heads)

There was no band in quite the same league as Talking Heads from 1977 to about 1984.  If you've never seen it, watch the concert film Stop Making Sense (1984).  Fair warning: if you don't already own every album in the band's discography before watching the film, you will purchase every album subsequently.  (It's worth your bank account taking a hit and you having to eat Ramen for a few weeks.  Trust me.)
My favorite Talking Heads album, Remain In Light (1980), falls smack-dab in the middle of that golden period of output.  The album is a non-stop tour de force of memorable melodies, polyrhythmic percussion, highly abstract yet highly literate lyrics, and producer Brian Eno's experimental sampling and tape loops.  It sounded like nothing else in 1981, and it still sounds otherworldly today.
Although it's difficult to pick out individual faves from the album, "Crosseyed and Painless" is a track that definitely shines.  The song is built around an Afrobeat rhythm, with cowbells and various percussion loops creating this undulating groove behind Chris Frantz's relentless drums and Tina Weymouth's gulps and slaps of fat bass.  (Side note: that woman must have callouses on her thumbs the size of grapes.)  It also features a guest spot by King Crimson guitarist Adrian Belew, who releases a buzzbomb guitar attack in the middle of the song.  (It's not a showboating type of guitar solo; nevertheless, it soars and wails in all the right places.)
Then there's frontman David Byrne's characteristically nervous vocals and a somewhat surprising "rap" at the end of the song (Facts are simple and facts are straight / Facts are lazy and facts are late...), which was inspired by Kurtis Blow's "The Breaks" (1980).
The song was released at the time as a promotional single with an accompanying video by choreographer Toni Basil (of one-hit-wonder "Mickey" fame), who used a Fresno, CA-based breakdance troupe known as Electric Boogaloos for the shoot.  I remember seeing the video ONCE on MTV2 sometime in the late 90s at like 2 am, and I didn't want it to end; it was like being zapped back to my childhood. 
I finally found the original video again on the interwebs for your (and my) enjoyment.
(P.S.  Dig the guy doing the moonwalk--a.k.a. the "backslide"--at the 3:30 mark, almost three years before Michael Jackson "debuted" it on the Motown 25 TV special!)