I use the notes section alot. I can store all kinds of related info.
For example on sites that still use a username to login, I can put the email I used to sign up in the notes section.
I'll also do security questions answers here. Using a pasphrase generator for those is good. No one is going to check if your first dog's name really was "consoling-roving-activator-earflap" and no one can find it on your over sharing grandma's Facebook.
I'll also attach any license keys/relevant files for software, now those stay encrypted and backed up with the database instead of in a random folder of text files.