Cup of Athelstan

The Cup of Athelstan was a historical treasure stored in the International Gallery in London. It was worth 18 million pounds. Lady Christina de Souza stole it in Easter 2010 and the travelled with her on a double-decker bus through a wormhole to another planet. The Doctor later uses it (and wrecks it in the process) to get the bus and the passengers onboard back through the wormhole to Earth. (DW: Planet of the Dead)