In the shower, I realized that I remember the entire theme song from Fight Back with David Horowitz.
FIGHT BACK! Don’t let anyone push you around
FIGHT BACK! Stand up and hold your ground.
And so on.
This got me thinking about other useless things that take up space in my brain, and I started humming theme song to Small Wonder, the witless 80s sitcom about a girl-robot, Vicki, whose family tries to keep her robot identity top secret.
Then I wondered if there was any useful stuff up there, which led me to what I remember from an entire year of high school geometry classes:
If a=b, and b=c, then a=c.
If a+b=c, then c-a=b.
Then I thought, Aveda soap smells just like Fruit Loops.