I mean REALLY big. If I saw one overhead I'd duck and cover. I can really see how something like this in the sky would spawn all sorts of stories, legends and other types of tales in impressionable folk. And with the size of this bird and it's sharp talons (up to five inches in length!!!) that would include, oh, just about everyone with a hind brain.
Wonderful photos, slightly disturbing "cycle of life" video involving a harpy eagle successfully hunting a sloth (poor sloth!) and a still of a harpy eagle eating a rabbit. Also, very interesting text about mammals and their warning calls, or lack thereof, for predators. Enjoy!
http://scienceblogs.com/thoughtfulanimal/2010/05/giant_birds_and_terrified_monk.php#more