A small keychain tool to blow through and focus air on your campfire to get it going - or maybe to keep that troublesome print from curling in that one spot.
Maybe a cosplay collapsible wand. A novel fidget also, I guess.
Either way, it was interesting to design and print.
Printed here 0.6mm nozzle, 0.2mm layers, PLA. No supports. Randomizing the seams helps, as there is a comfortable-yet-cozy 0.63mm between the cylinders.