The best thing about any charity shop is that you never know what you are going to find. I have a well tested route around London that includes all of my favourite charity shops. This Oxfam has a great selection of books and often turns up some interesting clothes too.
A beautiful and spacious (outside of rush hour) way to get from Highbury, through east London to south of the river in minutes. The train snakes epically through Hoxton and Shoreditch and opens up the Jubilee Line via the beautiful Canada Water / Bermondsey stations.
Although off the beaten track from the large national galleries, 198 is no less an important part of London’s artistic heritage. Developed during the social unrest in the Brixton area in the 1980s, 198 has grown from a community arts space into an exciting contemporary visual arts body that is often the first place to see the next rising star of the London art scene.