From the latest edition of the HB Direct newsletter http://www.dwp.gov.uk/housingbenefit/user-communications/hb-direct-newsletter/2009/issue-88-april-2009.pdf

"As part of DWP’s commitment to improving the access customers have to its services, the Department has developed the online Benefits Adviser service....In September this year the service will be enhanced with the addition of a calculation and comparison tool that will show customers how much benefit they could be entitled to. In addition to this it will provide them with the opportunity to input potential circumstances to see how this would affect their benefit, for example, if they would be better off in work."