of the Michael Crichton kind of novel, this story is definitely in the fact-stranger-than-fiction category (it's Mark Townsend Houston writing in the Observer):
It may be the oddest tale to emerge from the aftermath of Hurricane Katrina. Armed dolphins, trained by the US military to shoot terrorists and pinpoint spies underwater, may be missing in the Gulf of Mexico.
Experts who have studied the US navy's cetacean training exercises claim the 36 mammals could be carrying 'toxic dart' guns. Divers and surfers risk attack, they claim, from a species considered to be among the planet's smartest. The US navy admits it has been training dolphins for military purposes, but has refused to confirm that any are missing.
Alfred Nobel's father was an imaginative but impractical inventor who wanted to train seals to mine ships. (That's just an unrelated thought that comes out of my research for my new novel.)
(Link via Nico, who also sent the links for a truly demented set of pictures with a vaguely literary connection that have left me more or less speechless.)