Tulip Bulbs - For a while in Holland "The Currency"
http://en.wikipedia.org/wiki/Tulip_mania
At the peak of tulip mania, in February 1637, some single tulip bulbs sold for more than 10 times the annual income of a skilled craftsman. It is generally considered the first recorded speculative bubble (or economic bubble)
According to Mackay, the growing popularity of tulips in the early 17th century caught the attention of the entire nation; "the population, even to its lowest dregs, embarked in the tulip trade".[7] By 1635, a sale of 40 bulbs for 100,000 florins (also known as Dutch guilders) was recorded. By way of comparison, a ton of butter cost around 100 florins, a skilled laborer might earn 150 florins a year, and "eight fat swine" cost 240 florins.[7] (According to the International Institute of Social History, one florin had the purchasing power of ?10.28 in 2002.[33])
By 1636 tulips were traded on the exchanges of numerous Dutch towns and cities. This encouraged trading in tulips by all members of society; Mackay recounted people selling or trading their other possessions in order to speculate in the tulip market, such as an offer of 12 acres (49,000 m2) of land for one of two existing Semper Augustus bulbs, or a single bulb of the Viceroy that was purchased for a basket of goods (shown at right) worth 2,500 florins
Tulip mania reached its peak during the winter of 1636?37, when some bulbs were reportedly changing hands ten times in a day. No deliveries were ever made to fulfill any of these contracts because in February 1637, tulip bulb contract prices collapsed abruptly and the trade of tulips ground to a halt.[28] The collapse began in Haarlem, when, for the first time, buyers apparently refused to show up at a routine bulb auction. Only sellers existed, as there were no buyers, at all.