By Larry Ryan

How old do you think this man is? That's the question posed by The Age Project, a site which claims to look at "topics of aging, stages of life, and mortality".

The main feature on the site is their interactive game which gets people to upload a photo of themselves and asks you to guess their age. It is surprisingly difficult - in about 30 attempts I got only one right (twice I was out by about 20 years). Whether this actually meets the site's grand aims is debatable but it's certainly a highly addictive diversion when the afternoon slump kicks in.