Some songs just seem like they were made for each other.
Every time, and I mean every time, I hear “A Forest” by The Cure, I think of how amazingly it would mash up with “The Voice” by The Moody Blues. They’re somehow a perfect compliment to each other in my head. Maybe this is just me, but I can’t shake it. In the instrumental first 50 seconds of “A Forest” I always start singing “The Voice” to myself.
It’s quite possible that I have some bizarre sense of harmony that no one else would pick up on or agree with. But I find these imaginary mashups really interesting.