Couldn't think of any from D to I but here goes with J
JCR-UK (Jewish Communities and Records - United Kingdom)
This website contains some 5,000 pages including details of more than 1,200 congregations and includes current communities and those that no longer exist.
A joint project between the Jewish Genealogical Society of Great Britain and JewishGen
JEWISH EAST END CELEBRATION SOCIETY
Their aim is to raise awareness of the history and culture of London's Jewish East End, to preserve what remains and record what has now gone.
JEWISH EAST END OF LONDON PHOTO GALLERY
London's East End Synagogues, cemeteries and more.
JEWISH GENEALOGICAL SOCIETY OF GREAT BRITAIN
The JGSGB promotes and encourages the study of Jewish genealogy. It assists all those tracing the family history of their Jewish ancestors. It encourages Jewish genealogical education and research and promote the indexing, transcription and preservation of old records.