A number of buildings in London around the Thames are being illuminated with low-energy lighting for an event called Switched on London. The event raises the need to balance the importance of lighting in the nocturnal urban landscape with the need to save energy.
Being low-energy, some of the buildings weren't quite as stunning as I had hoped, but it's worth a stroll nevertheless. But you'll have to be quick; it finishes tomorrow, 14th February.
The picture is of Southwark Cathedral, but there are a few more in my set on Flickr.