While piracy has been a problem for many centuries, (real pirates at sea), Somali pirates have been taking over all sorts of boats lately, and people have had about enough of it.

One deterrent to piracy developed by the Coast Guard is equipped on the Littoral Combat Ship. It's a long, floating net that's designed to tangle up the prop of any boat that's unlucky enough to cross it. If pirates approach, they get stranded rather than taking you hostage. Seems like a pretty good alternative to me.

Via Danger Room