Liberty Belle

On April 1st, 1996, Taco Bell took out ads in 7 leading newspapers, stated they had bought the Liberty Bell to ‘reduce the country’s debt,’ and claimed they would rename it the 'Taco Liberty Bell.’ There were thousands of angry phone calls to the company, but the $300,000 prank generated $25 million of free publicity and over $1 million increase in sales in just 2 days. Source