The Harry Potter series has gripped the imaginations of multiple generations, and fans still hanker after any little piece of additional information they can find about the series. 

Luckily, author JK Rowling has a penchant for sharing fun HP facts via Twitter. 

In a recent thread about unusual things people have written their ideas on, JK Rowling offered this exciting titbit of information:

The author revealed that she came up with the concept for the various Hogwarts houses mid-flight.

This forced her to have to jot down the idea for the houses and their names on an aeroplane sick bag. Nice. 

This just kind of proves that the life of the multi-millionaire author wasn't always quite so glamorous. 

We're sure that these days she always has her Quick Quotes Quill on hand to note down any amazing new ideas that come her way.