I started doing a little research into this and found out that this...
Is the Croydon Crest. I Rather like it and interestingly the Latin motto 'AD SUMMA NITAMUR' means "Let us strive for perfection". Good Eh?
This
Is the "Croydon badge. This is what I found out about both these...
The flowering cross is derived, like that in the arms of the County Borough of Croydon, from the arms of John Whitgift, Archbishop of Canterbury during the reign of Elizabeth I, whose benfactions to the town include two schools bearing his name.
The crossed keys and swords refer to the Abbey of St. Peter and St. Paul of Chertsey, which was granted the Manor of Coulsdon in 727.
The keys also refer to the Abbey of St. Peter of Winchester, which acquired the Manor of Sanderstead in 964.
The heraldic fountain, from the crest of the old County Borough, is a symbol for water and refers to the source of the River Wandle. T
he branches of oak and beech are suggested by the two trees in the arms of Coulsdon and Purley UDC, where they refered to the wooded nature of the area and to Purley Oaks and Purley Beeches in particular. (That's where I live!!!)
The black lion (Remeber Lionhearts has been put forward as a suggestion) is also derived from the arms of Coulsdon and Purley and is a further reference to Hyde Abbey, the later name of the Abbey of St. Peter of Winchester, mentioned above.
The white horse is from the heraldry of the Earls of Surrey, the county in which the two constiuent authorities where formerly situated. The crosses formy fitchy are from the arms of the See of Canterbury and recall further the long association with the Archbishops, through the Manor of Croydon. Three such crosses appeared in the arms of the former County Borough.
I am not suggesting we just use these but they are a nice little piece of inspiration. I am going to start something but as a developer with only some design experience I am sure someone can take what I come up with a run with it!