Currently some countries ask for the new global currency to replace US Dollar. The exchange rate between US Dollar and Local currency in many countries are very unstable and causing many monetary crises. For example in Indonesia, in 1946 USD 1 = IDR 1.88. In 2009 the rate become USD 1 = IDR 12,000!
In 1970 the Pilgrimage (Hajj) cost in Indonesia only Rp 182,000. In 2009 it become naik jadi US$ 3.500 (Rp 36,750,000). The Rupiah value drops 201 times (20,100%!) in less than 40 years!
In Zimbabwe in 2003, USD 1 = 697.42 Zimbabwe Dollar. But in 2008 the rate become USD 1 =3.333.333.333.333 Zimbabwe Dollar! Inflation and prices change happen every hour ruining the economics! The funny thing is, Zimbabwe actually rich with natural resources such as antimony, asbestos, chromium, coal, cobalt, copper, gold, graphite, iron ore, magnesite, nickel, silver, and tin. Gold, chrome, and asbestos are the major mineral exports (Microsoft Encarta). With area of 390,000 km2 and population of 13 million people, Zimbabwe should be a prosper country. Yet, the “important” and uncertain of US Dollar value make all those natural resources worth almost nothing in dollar! The exchange rate is unclear. Set by speculators only.