If you like some nice cool beer, portuguese sweets (the once with yellow custard inside) tasty and affordable sandwiches, good strong coffee and football, at all hours. Max Snack Bar is worth checking out.
I am definitely not precious about the materials I use to make my work, but every so often I find myself in need of something more specialised. L.Cornelissen & Son is a beautiful and well stocked art supply shop with extremely knowledgable staff.
The most amazing little shop selling natural, organic preserves by the wonderful Lillie O’Brien (ex St John Bread & Wine pastry chef). Super friendly staff and insane jam doughnuts!