The coloured piece on the left is by Psychonautes and is called "Angry". The black and white work on the right is by OneR and seems to be called "Night Call".
The next, more colourful, piece is also by OneR. It's on the front of the Camden Palace Hotel. It's around a bit longer. I took these pictures in October 2013.
Psychonautes also has a couple of large skull paste ups put up across from the Camden Palace on Pine Street. I took these pictures in October 2013.
FYI: other views of the Psychonautes pieces can be found on his Flickr pages at the following links: