Technically it is known as the fruit from a Bunya-Bunya, or Monkey Puzzle tree. Dickiebo mentioned these on his blog. The fruit is a very, heavy, solid cone. They make quite a thud when hitting the ground or roof.
Anyway, in a comment on dickiebo's blog, I promised to post this picture. (I may have posted it a year ago or so. Haven't checked) There you have it.