Essentially the site uses several datasets to allow you to build up a picture of what life may have been like within an area of London at a particular time. Choose a dataset and then use a series of powerful filters to control the search eg. women killed in a particular street in a particular year.
Old Bailey Proceedings
Hospital and Guild
London Lives Additional Datasets
Four Shillings in the Pound Tax
London and Westminster Directory
St. Botolph Aldgate Parish Registers
Westminster Historical Database (ratebooks)
Westminster Historical Database (votes)
Centre for Metropolitan History
Museum of London Archaeology
Population and Area Data
Interesting if you have a London connection, and free to access. The programme this morning also noted that the model employed could be used for other areas of Britain, though no details were given as to whether this was actually on the cards or not.