Probably a boring answer but I know my grandmother’s credit card information. I live with and help take care of her, so she doesn’t mind sharing it with me. Not like I’m planning to do anything nefarious, but I guess technically it could ruin her financially.
It’s the custody agreement part that I’m wrestling with, though I’m sure if I just ran off with the kids I’d hit kidnapping and Interpol issues too. That’d be exciting, though unlikely to be a productive outcome all around.