It's Thursday, so you know what it means, Neatoramanauts: it's time for the What Is It? Game, brought to you by the wonderful What Is It? Blog.

What is this thing in the picture? Your guess can win you a free T-shirt of your choice from the NeatoShop! Here's how to play:

Place your guess in the comment section below. One guess per comment, but you can enter as many guesses as you'd like in separate comments. Post no URLs or weblinks.

You might know what they are, but if you want to win a t-shirt, you'll have to use your imagination, because we are going to select two winners who give us the funniest incorrect guesses. If you guess right, you may get a pat on the back, but you don't win anything, see? So get creative!

Please write your T-shirt selection alongside your guess. If you don't include a selection, you forfeit the prize. We suggest you take a look at the NeatoShop's selection of Funny T-shirts and Science T-Shirts. Or maybe a Sci-Fi Shirt! Or a Pun Shirt!

Visit the What Is It? Blog for for an additional picture of this thing. Then enter!

Update: This is a replica Confederate torpedo for guarding their harbors from Union ships, they "were constructed from available wooden barrels, then filled with gun powder and fitted with a contact detonator. Streamlined ends were added to lessen the effects of tides and currents. The Union Navy lost more than 40 ships to these torpedoes." The actual size of these mines was three to four feet long. A lot of your guesses were right, or dangerously close to right, but we were looking for funny but wrong answers. One of the funniest came from moddycurl: “This is the actual dressmaker's form used to make several of Madonna's costumes.” That’s worth a T-shirt from the NeatoShop! Bo Culjan had a great one, too: “It's the collar attachment for the "Dogs of War" model St. Bernard.” That one deserves a T-shirt, too! Congratulations! Thanks to everyone who played this week. You’ll find the answers to all this week’s mystery items at The What Is It? blog.