Make sure to use a reputable IT recycling company, it's worth spending a bit of extra foot-work or money and finding one who can securely AND ethically dispose of your equipment.
Even with the strict WEEE legislation in the UK, many companies are falling victim to man-in-a-van outfits. Do your research and make sure your old equipment and data is disposed of correctly.
http://www.uk-computer-recycling.co.uk