Photority

Open to all UK photographers - professional and amateur - 16 years and over, the Urban Photographer of the Year will be chosen as to who can best depict the competition’s theme “CITIES AT WORK”.
The objective is to explore work life in the UK’s towns and cities during any single hour of a 24 hour [...]

There are 4 rounds to the Crestock Photoshop Contest 2007 but since the submission of the first 3 rounds are past due, then I’ll just give you details for the 4th round.
Round 4:
December 4, 2007 : Source images released & submissions open
December 11, 2007 (10:00am GMT/ 02:00am PST): Submission deadline
December 11, 2007: Voting opens
December 18, [...]