This pair of rubbery Sumos will tumble down any window. Their slightly sticky exterior means then when you lob them at a pane of glass, they'll stick, then slowly tumble down.
You can try racing them, or squidge them together and watch them tumble in tandem.
Each Tumbling Sumo is about 6 cm high. Keep these little guys clean. If their surface gets grubby they'll drop not tumble. Sumos can be washed in water to clean them.