Apart from clothing, knickknacks and local snacks, there is one item that you may have trouble finding outside Turkey: cesm-i bulbul, a type of glassware whose name means "nightingale's eye."
Though there is some disagreement about cesm-i bulbul's exact provenance, Turkish cultural historians agree that near the end of the 18th century, Sultan Selim III sent a noble named Mehmet Dede to Venice to learn glassmaking techniques. Upon his return, Mehmet Dede opened a workshop in Beykoz, on the Asian side of the Bosporus.
One technique he brought back - in which colored glass rods are wrapped around molten glass - was refined into cesm-i bulbul. Today his successors make pitchers, decanters and even hookah pipes in clear or white glass with fine stripes of blue, cyan and white.
There are two main outlets for cesm-i bulbul: the Pasabahce stores - one of which is at 314 Istiklal Caddesi, (90-212) 244 0544 - owned by Sisecam, a Turkish glass giant; and the Glass Furnace, (90 216) 433 3690, a workshop and educational center near the village of Ogumce in Beykoz. Both companies' wares are handmade. The pieces are often delicate, with vessels made in lithe Ottoman shapes, sometimes with undulating edges.
"We try to keep the color and the shapes traditional, because people prefer that more than the modern style," said Aydan Oner, the product manager for Sisecam. She said the products on sale were based on the company's own 18th- and 19th-century collection, which may soon be displayed in a museum.
In the busy Pasabahce store on Istiklal Caddesi, the cesm-i bulbul sits alongside other exotic glassware, modern home furnishings and even funky design furniture as attendants in smart red aprons zip to and fro. Prices range from $30 (at 1.4 new Turkish lira to the dollar) for a fluted vase to $175 for a set of six glasses and a carafe.