CompanyCheck – Free UK and Ireland Company Information
http://companycheck.co.uk/

Find free company information on any business or director in the UK and Ireland. With over 30 million records, Company Check is the largest source of free data in the UK and amongst the top 300 most visited websites. They deliver over 50,000 sets of Accounts, 90,000 email alerts and 2,000,000 company and director credit reports every month. Over 250,000 users have already signed up. This has been added to Business Intelligence Resources Subject Tracer™.