A red clip
Here is Ginza, one of the biggest shopping districts in Tokyo.
A sigh board on the left is the one of stationery shop, called Itoya. A red paper clip have been the trademark of this shop for a long time.
Perhaps as you know, an young American, Kyle MacDonald, traded one red clip for a house. He started with one clip and 14 trades later, trade for a house.
How many times does it take to change this big clip for a house?:-)