Location Maps
Street Map - http://www.streetmap.co.uk/
Google Maps - http://maps.google.com/

Handy Currency Converter - http://www.xe.com/pca/

Travel
National Rail Information - http://nationalrail.co.uk/
Rail link from London Heathrow - http://www.heathrowexpress.com/
Rail link from London Gatwick - http://www.gatwickexpress.com/
Rail to Paris, Brussels and beyond - http://www.eurostar.com/
Travel around London (Oyster Cards) - http://www.tfl.gov.uk/

Museums:
Natural History Museum - http://www.nhm.ac.uk/
Victoria and Albert Museum - http://www.vam.ac.uk/
Wallace Collection - http://www.wallacecollection.org/
The Science Museum - http://www.sciencemuseum.org.uk/
The British Museum - http://www.britishmuseum.org/default.aspx

Galleries:
Hayward Gallery - http://www.hayward.org.uk/
National Gallery - http://www.nationalgallery.org.uk/
National Portrait Gallery - http://www.npg.org.uk/
Royal Academy or Arts - http://www.royalacademy.org.uk/
Tate Britain - http://www.tate.org.uk/britain
Tate Modern - http://www.tate.org.uk/modern

Places of Interest & Royal Family:
Official Website of the British Monarchy - http://www.royal.gov.uk/output/Page1.asp
Historic Royal Palaces - http://www.hrp.org.uk/
Tower of London - http://www.camelotintl.com/tower_site/index.html
Tower Bridge - http://www.towerbridge.org.uk/TowerBridge/English
Westminster Abbey - http://www.westminster-abbey.org/
Houses of Parliament & Big Ben - http://www.parliament.uk/
St Paul's Cathedral - http://www.stpauls.co.uk/page.aspx?theLang=001lngdef&pointerid=169345dwprEOVViTRLd8xXbHBDHGbzge

Around London:
London Tours - Private guided and group sightseeing tours to London, Windsor and Hampton Court in England, United Kingdom - http://www.londonmagicaltours.com/
London Eye - http://www.londoneye.com/
General - http://www.londonpass.com/

Entertainment
The Timeout Guide - http://www.timeout.com/london
BBC London Website - http://www.bbc.co.uk/london/entertainment
London Evening Standard - http://www.thisislondon.co.uk/
View London - http://www.viewlondon.com/

Theatres
London Theatre Guide - http://www.londontheatre.co.uk/
Society of London Theatres - http://www.officiallondontheatre.co.uk/
Ticketmaster - http://www.ticketmaster.co.uk/
Last Minute Tickets - http://www.lastminute.com/site/entertainment/theatre
Cinema - http://www.ticketmaster.com/film/cinemas