Calamity Lamp
From Tardis Wiki, the free Doctor Who reference
Calamity Lamp A Calamity Lamp was a device used to send distress signals into space, a sort of "message in a bottle".
Sweetleaf send a Calamity Lamp across space to call for help as her world was being demolished by the High Goliax, the biggest bank in the Universe. (DWM : The Woman who Sold the World)