Portugal is the world's largest producer of cork, and it takes that versatile material to a new creative level. At Cork & Co. or Pelcor in central Lisbon, you can pick up cork-based jewellery and accessories, which make for unique souvenirs. There is plenty of scope for upscale shopping on Lisbon's famous Avenida da Liberdade, which is lined with designer stores like Louis Vuitton and Prada.