I’m always curious to hear any information that suppports the argument that not making your site accessible is a nonsense. The DDA Centre has nothing to do with website design, but they did have this little snippet on their website:

Disabled people have an annual spending power of 50 billion pounds a year. There are approximately 8.6 million disabled people in Britain.
Source: Regulatory Impact Assessment, Access to Goods, Services and Facilities, Disability Discrimination Act, Department of Work and Pensions, July 2001

Essentially, it is now so easy to make your website accessible, that you’re just chucking customers out the window by not making the effort…