Blue points us to this story about how Cho Seung-Hui took a break between bullet-spraying episodes to mail in a DVD containing disturbing images, video, and a 'murderer's manifesto'. Here's a NYTimes story on this psychopath.
Barbara Oakley recounts a scary episode from her academic life, and raises questions about how the universities usually handle potentially dangerous students. However, privacy laws in the US leave universities with little leeway in dealing with mentally troubled youth.
Gawker compares "the routes ... followed by various trains of thought after their departure from their respective stations of nationality and ideology." Very perceptive.