I was feeling down this morning - not about anything specific, mind you, just generally sort of stressed and overwhelmed and overall blue.
So I started singing the Fraggle Rock theme song to myself and immediately felt better.
My current fav version of it (other than the original, of course):
https://open.spotify.com/track/2As89VjjlMGJHZZA9O6p7f?si=f5cff707ebd54c84