Probably one of the more strange ones that took me forever to figure out was Matt Kearney's "Nothing Left To Lose" which is a pretty common 4/4 song, that throws a 3/4 curveball in the middle of each chorus.

https://youtu.be/a7YP4k7rMuc

When I was learning this song for ye olde guy with a guitar coffeehouse performances it took me way too long to figure this out and I was always out of sync with the song.

I mean, c'mon, this guy is just a plain vanilla Coldplay wannabe guy right? What's he doing throwing that in there?

Because it is what grabs the ear and makes the chorus just a little bit more catchy. Just make sure where to switch to 3/4 and you're good.