The London Perambulator is a wonderful short documentary about walking in London's fringes. Although it was made in 2009, I've only just come across it. Directed and shot by John Rogers it focuses on Nick Papadimitriou and his walks on the edges of London.
It includes interviews with Will Self, Iain Sinclair and bizarrely Russell Brand. A lot of the discussion focuses on the psychogeography and deep topography of London; two terms I've never heard of before, but something I can certainly relate to on my tube walks.
I won't spoil any more of it here, you'll just have to watch it.
For more visit The London Perambulator website.