I've given up on figuring out "effect" versus "affect." Which is an embarrassing brain glitch for a writer.
Also, I've got a black hole in my brain where the math should be. This is very frustrating, because so many of the things that interest me (like quantum physics) requires a gift for math to truly understand.
Here's mine: I have no freaking idea what the term "hump day" means. I keep reading it and thinking it means today you get to hump and that's why everyone is happy when they post that it is hump day.
Hump Day is Wednesday. It means that you've gotten over the hump and it's all downhill from there. It's not really an accurate metaphor.