The Doomsday Book is the record of an in-depth survey of England and Wales completed in 1086. It’s purpose was to establish material wealth of land owners and create a record of tax liability after the Norman conquest of the country.
For the first time the entire book is available online. Every place mentioned is marked on an interactive Google Maps, and shown alongside scans of the original, with information about population and assets translated from latin into English. domesdaymap.co.uk
Back in 1986, to tie in with the 900th anniversary of the original book, the BBC recorded a snapshot of everyday life across the UK. Unfortunately it was stored on the expensive and soon to become defunct Laser Disc format, meaning it remained inaccessible for many.
25 years later you can now explore a map of the archive online, see photos, read accounts of daily life, and submit updated information: Doomsday Reloaded. The BBC has further background information about the project.