The article, "World's tiniest submarine emerges from Down Under" shows a submarine built by australian researchers, claimed to be the smallest in the world. Serfina, its designers say, has been built with the intent of shipwreck recovery, though it could have military uses. And whats more, according to its Chief designer Dr. Uwe Zimmer, its development and production cost were a fraction of the real thing - US$ 700.
The only concern the designers have it that serafina could be eaten by sea animals. Now u know why it reminds me of the movie ;)