In Spain researchers have unearthed the fossil skeleton of a giant rabbit. It was found on the island of Minorca. It is said to have weighed 26.4 pounds and is between 3-5 million years old.
It was so big that it most likely lost its ability to hop.
and here: http://www.cbsnews.com/stories/2011/03/21/scitech/main20045568.shtml