Some misprinted U.S. coins can be sold as collectibles at many times the face value. The value of a 1969 Lincoln penny with a "doubled die" is approximately $35,000, according to About.com.
Other coins with errors from the U.S. Mint are worth $5 and up depending on the number of coins printed and the type of error. Mint Error News provides a price guide and notes that prices fluctuate. It advises consumers to check several pricing resources before attempting to sell a coin with an error.
Mint errors fall into several categories based on issues with the die or how the coin was struck, and some coins may have more than one type of error. A coin with differences from its typical design may be a variety rather than an error.