Which is the most expensive penny?

In Extremely Fine condition, it would have to be the 1807 Large Cent. There was a die error that put the value of this "large" penny valued at $24,000.00.

Updates

A lot has changed since the first answer was written. As of 09/2011 the top spot has been taken by a bronze 1943-D cent in MS-64 condition, with a retail value a bit under $2 million.