From the blog Nuclear Reactor, someone has built a nuclear reactor in Minecraft and had it explode.
In real world nuke reactor news, Europe is set to dismantle 150 nuclear reactors over the next 20 years: for the Washington Post, Brad Plumer reports on the difficulties of decommissioning nuclear reactors, both financial (400 million — 1 billion dollars per plant) and logistical in “How Hard is it to Dismantle 150 Nuclear Reactors? Europe’s About to Find Out.”
And some nuke reactor pics:
3 Mile Island
The Hyperarchival Parallax 
For those interested, a Minecraft modification called IC2 contains the nuclear reactor/bombs (and a lot of machines and generators for automation) shown in the video above. If you don’t know how to install mods in Minecraft, look up an advanced mod pack called Tekkit that has a auto-installer and won’t mess up your normal Minecraft install.