To have a hit of feel-good music at the ready is especially important right now because man, the YA novel I'm currently working on is sad. And it's both crying out for me and pushing me away with both hands. Inconsolable is what it is.
Hmm, maybe I'll add another feel-good tune for good measure (Incidentally, Abba and I go waaaay back. The first pop album I ever had was one of Abba's greatest hit albums).