This is one of those pointless but cool gadgets that I love. A pen with a built in shredder.
You can scribble your secret doodles and then as soon as you hear somebody coming shred the evidence. I would get one but there is no point as I’m certain my daughter would pilfer it (in a friendly) before I got it out the wrapping.
More info at radicauk, found via Shiny Shiny. Oh and it contains an FM radio too, obviously!