Zeiton
From Tardis Wiki, the free Doctor Who reference
Zeiton was a class of mineral and fuel which was used by TARDISes, types of which included Zeiton-4 and Zeiton-7. The Tenth Doctor fired up the Zeiton crystals as one of the steps to keep his TARDIS and his fifth incarnation's TARDIS from blowing a hole in the space-time continuum. (TV: Time Crash)
