I saw this article on Yahoo! and it reminded me of my family's experience at a Zimbabwean market three years ago. While we there, the shopkeepers preferred to take U.S. dollars or South African rand instead of their own currency. (They even preferred pens to their own currency.) Now the Zimbabwean government has made U.S. currency legal tender in the country. People exchange the money so much that they have resorted to machine cleaning the bills to keep them in circulation.
Oh, Zimbabwe. How I hope things can change for your people soon.