Ten tube stations have signed up to the 10:10 pledge (cutting your carbon emissions by 10% during 2010). Bank, Charing Cross, Earl's Court, Green Park (appropriately), Holborn, Hyde Park Corner, Knightsbridge, Liverpool Street, Moorgate and Victoria will get initiatives like new switches and sensors, so lights can be turned off in areas that aren't in use. (This came as a bit of a shock to us; we kind of assumed when the shutters came down, the bulbs went out.)
Escalators will also be turned off out of peak hours so if you have to walk at some of these stations - remember you're doing your bit for the environment (and getting some exercise). And of course, saving energy also means saving money - and when it comes to TfL's budget, every little helps.