Anoraks, geeks, nerds - there's no shortage of insults for enthusiasts who take their interests just a bit too far. But a new report suggests these fanatics are a growing force in society.
Obsessives could be an asset to society
Seb Potter is a hidden cog in the feverish global economic engine. The 27-year-old regularly gives large chunks of his leisure time to building "open source" software.
One of the projects he contributes to has helped power websites for the likes of Nasa and the Strategic Rail Authority. Yet he's not received a penny for his work.
Mr Potter is one of a growing army of serious enthusiasts whose dedication to a pastime is making a significant contribution to society, according to a new report.
Typically called hobbyists, nerds, anoraks or geeks - the commitment of such people should be harnessed rather than derided, according to the report by think-tank Demos.
Calling them "Pro-Ams" - amateurs who pursue a hobby to a professional standard - it suggests such people should receive government funding to "promote community cohesion".
Growing affluence and the trickle-down of specialist technology has allowed people to practise hobbies such as astronomy and photography to a standard that previously would only have been achievable by professionals.
"The internet has brought disparate groups of like-minded people together to discuss their hobbies and share ideas," says Paul Miller, a co-author of the report.
"Access to information is one of the main reasons Pro-Ams are becoming more important. The internet also provides a forum for them to compare their abilities with others. It can be pretty competitive."
More than half the population regularly engage in Pro-Am activities, but within that is a hardcore of those who believe they are exceptionally good, and judge themselves by expert standards.
The report defines Pro-Ams as "amateurs who pursue a hobby or pastime - which in many cases is an all-consuming passion - to a professional standard". In a climate of rising stress levels at work Pro-Ams seek relaxation and reward in their hobby, says Mr Miller.
"In the 1990s job satisfaction statistics fell markedly. People sometimes refer to their Pro-Am hobby as their 'shadow career'."
Men are more likely to be Pro-Ams than women, and they will tend to be well educated from households with an annual income of more than £30,000.
Traditionally, Pro-Ams have made a valuable contribution to society as lifeboat volunteers or Samaritans, but their sphere of activity is widening, as the example of Seb Potter illustrates.
TOP PRO-AM ACTIVITIES
4. Arts and crafts, eg painting/pottery
A computer programmer by day, Mr Potter has been using his professional skills to help build and refine "open source" software for six years.
He is one of about 100 contributors around the world developing a program called Plone which stages websites.
"I just really enjoy it. It's like giving something back to your community, albeit that it's a global community rather than a local one," he says.
Is he troubled by the fact that big organisations are using his free program? "I think it's great. We want to try to get maximum exposure because the more people that use it, the more others will find out about it."