Here is a fascinating article about DARPA's "high risk, high payoff" quest to develop an exotic new Hafnium bomb -- a new kind of weapon that emits huge amounts of gamma rays from a very small package. This thing packs the bang of a conventional nuke in a package as small as a hand grenade -- and the gamma ray burst that results can penetrate deep into bunkers and through thick materials. Of course, it would really be a bad idea to toss a Hafnium grenade unless you could run incredibly fast. But that said, Hafnium weapons may be a big part of our future (or who knows, maybe they're already part of our present?). Beyond military applications, it seems this technology could offer a very promising new non-fossil fuel energy source, if it weren't so expensive to produce.