In my fourth book, SKY SONG, a standalone adventure set in a snowy kingdom called Erkenwald, there is an inventor boy called Flint. I had a lot of fun writing about inventions Flint might have come up with - hammocks spun from moonlight which grant glorious dreams, lanterns containing sunbeams which burn through the winter months - and now I want YOU to make up an invention of your own.

What does your invention do? How does it work? Does it require ingredients stirred in a large cauldron? Or maybe strange items collected under a full moon? Who uses it? Does it have a name?