Ghosts and the like. Please feel free to add both weblinks and wiki words.
City of Shadows has some historically-oriented but rather eclectic information.
See Gaslight for some contemporary fiction.
Consider also The Ghost Club, founded 1862, which continues to investigate hauntings to this day. Their list of links is certainly worth browsing.
Mysterious Britain is interesting, but at the moment there are no hauntings listed in London!
-- ChrisLehrich? - 29 Dec 2004