This crest of the City of London is my entry into the "London Calling":http://www.redbubble.com/groups/redbubble/challenges/933-this-is-london-calling Challenge.
ARMS: Argent a Cross Gules in the first quarter a Sword in pale point upwards of the last.
CREST: On a Wreath of the Colours a Dragon's sinister Wing Argent charged on the underside with a Cross throughout Gules.
SUPPORTERS: On either side a Dragon Argent charged on the undersides of the wings with a Cross throughout Gules.
MOTTO: "Domine Dirige Nos" - Lord, Direct us.
Thanks to "this guy":http://www.civicheraldry.co.uk/ for the write up.