If you like fashion then this is the place to be. The label was founded in 2005 by Nando and Silvia, two spanish designers. I like this place because I love the wool coats and the patterns they create. They support local industry and that is a top of the top for me.
While strolling around Mitte, check out the flagship store of Berlin´s cult women fashion brand. (And try a delicious cinnamon bun at Zeit für Brot next door.)
It is an English language bookstore centering on non-western, diasporic, and queer perspectives.
Many many many rare and special books carefully selected by Siddhartha Lokanandi that is the soul of this place! Check it, it is unforgettable :)
A place where I spend some time almost everyday is the Marheineke Markthalle on Bergmannstraße in Kreuzberg. It's just around the corner from where I live and a great place to buy fresh food and products from local farmers or all kinds of delicatessen from different countries. Many market stalls also sell freshly prepared food and it's always busy at lunchtime. For saturday mornings try the original french croissants.