"The woodpecker's long tongue, in many cases as long as the woodpecker itself, can be darted
forward to capture insects. The tongue is not attached to the woodpecker's head in the same way
as it is in most birds, but instead it curls back up around its skull, which allows it to be so long."

Wikipedia, http://en.wikipedia.org/wiki/Woodpecker (as of January 26, 2008).