public transport is half price when using an Oyster card (
https://oyster.tfl.gov.uk/oyster/gue...method=display).. and buses in the centre of London won't accept cash..if you plan on getting around you need a card or at least a weekend pass which you can buy at train/coach stations and some newsagents
the cheap theatre tickets at Leicester Square are usually sold out before 1pm....like has been said all the museums are free as is the Tate Modern Gallery.. or there's always the usuall "northerners" weekend in London..a pub crawl around Soho
mind you Soho does have a fruit n veg market thats as cheap as anywhere in the country.