Oh, I remember that one strongly. mira_kitty often reminds me of it when I observe her staring fixedly and wide-eyed at some point high on the wall behind my bed, perhaps moving the point of her stare now and then. I look, and see no bug or anything that might concern her. So I turn back. But I see her staring some more. Uncomfortably, sure I must have missed the big bug she's staring at, I look back again. Nothing. I turn back. Then I see that fixed wide-eyed stare again.

I know she's either just intentionally messing with me, or she is truly Seeing Things We Can't. Spoooooky!