I keep a notebook (or a substitute) by the bed, for the very same reason. Writing most ideas down is worth it, in a sense of developing a habit to write all of them down, regardless of how much they're worth at the time.
I'm writing this story, where chapters are broken down by the song the main character listens to, which reflects his emotional state. I've had this great song idea for a sudden shift in atmosphere when his abuse ex messages him out of nowhere, after years apart. It's an emotional whiplash for the character.
I'm kicking myself for not writing the title down. All I remember now is that it was perfect for it.
