You can buy fans anywhere in the world, but Japan is the (unofficial) home of fans and they are closely associated with the culture. Who hasn't seen the image of the beautiful Japanese woman holding a fan in front of her? Every summer, a wide variety of attractive, cheap, and free fans are available. You find plastic ones featuring ads being given away on the streets for advertising as well as special promotional ones being offered at festivals and shops. You can buy many different kinds at 100 yen shops, or visit some of the better souvenir shops and buy more elaborate ones. In the summer, they are a compact and ecologically sound way to cool yourself down, and they are just plain nice to display if you are of a mind to do so. They also make nifty souvenirs for folks back home.
I'll miss the abundant Japanese fans.