This video is circulating around Myspace and probably via email by now.

Of course, I checked out the validity.
Supposedly, this video is not confirmed to be real or not, yet...

This page takes you to snopes, the video does not immediately play. You must click play to see it. I advise against watching....

For more info:

http://www.snopes.com/photos/military/throwpuppy.asp

ETA: apparently the video on snopes is no longer available.
If you must see, its here, but it plays as soon as the page loads. You were warned.

Personally, I am curious to see what action the government will take IF this is real...

http://www.tosspuppy.com