UpMyStreet.com: http://upmystreet.com
An interactive site which highlights differences between areas in terms of social structures. Enter a postcode or a name of a town and a page will appear that displays data on that area. Data includes unemployment statistics, house prices, council rates, and local community services. An indication is also given of likely rates of consumption of selected categories of products.

Office for National Statistics: http://www.statistics.gov.uk
UK National Statistics web site, with summaries of numerous surveys of population characteristics, lifestyles and attitudes.

The Future Foundation: www.futurefoundation.net
A research organization that produces reports on the likely future shape of the consumption environment facing businesses, including the effects of social and demographic change on market segments. Many reports or abstracts are freely available.

Oxford Institute of Ageing: http://www.ageing.ox.ac.uk
This site provides some interesting insights into the changing consumption patterns of segments of elderly consumers.

Presky Maves Group: www.quantpreskymaves.com
A consultant's web site which provides interesting case studies of segmentation applied to direct marketing.