While browsing around after watching The Christmas Invasion I disovered some rather interesting websites. For a start, there's the one for UNIT set up for Aliens of London. But there are also sites for GeoComTex (Henry Van Statten's company from Dalek), the British Rocket Group (which features in The Christmas Invasion), and Mickey's Who Is Doctor Who? conspiracy site. Plus (of course) the Big Bad Wolf.
Anybody know of any others I should check out?