A Swedish artist, Sanna Dullaway, works with some old pictures and colourises them. She does restoration work and on occasion colourises old photographs of well known people. What superb work! Here is are links to some of her work and sites where she shows colourised photographs.
Link via imgur.com 
Here is Sanna Dullaways’ flickr album for colourised photographs from black and white…
Colourised black and white photos
And, here is her album for restored photographs…
Restoration photographs by Sanna Dallaway
See Sanna Dullaway on ‘deviantArt’…
“MyGrapefruit” on Deviant Art