Le Marche aux Fleurs on Ile de la Cite puts vintage to great effect on their flower displays. Lots of mirrors, old stripped dressers and lots of quirky pots.
Le Brasserie Terminus Nord opposite the Gare du Nord, is full of original nouveau and deco style and fittings - book 'Le Salon' for a very special private dining experience with the most fantastic windows, and a huge portrait of (I think), Sarah Bernhardt.
All of the Brasserie Flo have a unique history, and Julien - within walking distance of Gare du Nord, is decorated in the most stunning, original 'Belle Epoque' decor. The food is sumptuous too, and service by real waiters dressed in black and white with long white aprons. Bliss.