The powers that be have been secretly planning a replacement for our dollar, the Canadian Dollar, and the peso. Its name is the Amero. An excerpt is taken from the government's documentation:

The Canadian dollar could be linked in value to the U.S. dollar; Canada could adopt the U.S. dollar; or a new North American currency (called the Amero by one proponent) could replace the U.S. and Canadian dollars, and perhaps the Mexican peso.

Source: http://ottawa.usembassy.gov/
francais/fr/content/can_usa/trade_crs_050206.pdf

To be sure that the source file is not removed from their site, a copy is saved on this server. trade_crs_050206.pdf