This may not be much of a secret but deserves a mention. I find it hard to go anywhere near this place without having to go there. Freshly baked Beigels hot salt beef and it never closes, 24 hours a day 7 days a week.
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.
Great little cinema, hidden away in the basement of Aubin & Wills, London. Not exactly a fan of the brand but the cinema is pretty awesome. They show a variety of interesting films and have probably the comfiest seats including armchairs and sofas. Bit dear, but one of the best cinemas I've come across.