Check out the eerie melancholy guitar and piano music at the end of this video. I keep playing it over and over again. https://tinyurl.com/3kvr6uv6Its an anti-drug video and you have to sign in to see it, so beware.
hxxps://www.youtube.com/watch?v=qIx6p0u9Lkg&t=1050s
xx = tt
clicking this works ---> 17:30
At about 18:52 one of the credits displayed is
Music
JONATHAN XAVIER COUDRILLE
That guy's whole channel is mashups. There are some incredible ones.
Mashups used to be music only, then a few artists like 'GirlTalk' (among others), incorporated video mashups to match. Now with so much video editing software/apps available, they have become a standard part of a lot of mashups.
Here is an early version done several years ago...
...and a couple more unlikely, but incredible pairings.