from snopes:
To pay off a billion dollars in nickels would require 20 billion of those coins. That amount would require Samsung to obtain the equivalent of all the nickels struck by the U.S. Mint in the last several decades. (In 2011, for example, the U.S. Mint produced less than one billion nickels, and 2010 less than half a billion.) Samsung would have to round up virtually every nickel in circulation to acquire over $1 billion worth of those coins, a feat that could hardly be accomplished without having a significant impact on the U.S. monetary system.
A single nickel weights 5 grams (about .011 pounds), so a billion dollars' worth of nickels would weigh in at about 110,000 tons. That load would far exceed the carrying capacity of 30 or so trucks (requiring each truck to carry over 3,600 tons, or more than 7.2 million lbs. each). Even if the considerable weight of the trucks themselves weren't taken into account, the equivalent of about 2,755 eighteen-wheeler trucks, each hauling 40 tons' worth of nickels, would be needed to transport the weight of that many coins (and even that calculation still doesn't take into account the volume of physical space needed to assemble, transport, and store 20 billion nickels)