From Tom Carden – not official TfL, just “proof of concept”
“Click on (or select, above) a station to see the London Underground map reorganise around the times of travel from that station. Shortest paths are used to place the other stations – radius is proportional to time to travel, and angle should be correct for as-the-crow-flies direction on a map. The concentric circles are at 10 minute intervals. Press ‘g’ to get back to the geographical tube map”
It does make you rethink the distances on the original (brilliant) Harry Beck map.