Ron Paul has another reason why we need competing currencies:
Statement before the Financial Services Committee, Subcommittee on Domestic & International Monetary Policy, Hearing on Examining Issues Related to Tactilely Distinguishable Currency, July 30, 2008
We would not be here discussing this topic today if we had a truly free monetary system. It is well known that I am a proponent of sound, commodity-backed currency. Anyone who has ever felt the heft of a gold or silver coin, noticed the variation in size and design among different denominations of precious metal coins, or examined the different types of reeding, incusing, and other edge designs, recognizes that coins are far superior to paper bills in terms of their ability to be distinguishable solely by touch.
Due to what many people deem the impracticality of carrying around coins, paper bills have over the course of time replaced coins in everyday commerce. However, a system of competing currencies would ensure that blind or near-blind citizens have access to currency. If we had a truly free market in currency, private currency producers could produce coins or bills that are tactilely distinguishable, with bills incorporating different sizes, shapes, raised geometric patterns, etc. It is not inconceivable to imagine that a privately issued currency incorporating such features and making itself available to all Americans might obtain a dominant position as a preferred currency.
What prevents such a scenario from occurring is the US government's attempts to maintain the monopoly of the dollar. Through a multifaceted legal barrier consisting of legal tender laws, anti-counterfeiting statutes worded to prevent the private issue of notes and coins, and punitive taxes on precious metals that would form the backing of a commodity-backed currency, the government has ensured that alternative currencies, such as the Liberty Dollar, have to face an often insurmountable legal hurdle. While nothing prevents many point-of-sale transactions today from being carried out in euros or pounds, legal tender laws ensure that Gresham's law, that bad money drives out good, remains in effect.
The recent court ruling against the Treasury Department has been advertised as having a potential cost in the hundreds of millions of dollars. It would be far more economical to eliminate the legal restrictions on private currencies and enable the market to find a solution to the problem of currency for the blind. Competitive private currencies would have the added benefit of keeping the US government honest by forcing the government to stop the limitless increase of money, which is inflation, thereby removing the government's ability to run up large trade deficits, half trillion dollar budget deficits, and an enormous national debt. Allowing currency competition would aid in lifting burdens not only from the blind, but also from all American taxpayers.