The Backstory of the Kaminsky Bug
Ant recommends a Wired piece on the background story of the Kaminsky DNS bug and its (temporary) resolution, decreasing the odds of a successful breach from 1 in 2^16 to 1 in 2^32. We've discussed this uber-hole a number of times. Wired follows the story arc from before Kaminsky's discovery of the bug to his public presentation of it in Las Vegas.
Go check out Kaminsky's powerpoint of the whole thing. It's actually a very, very serious bug. I warn you, its 107 slides, but a few dozen into it and you'll see the danger he uncovered.