A group of researchers have shown that it is possible, perhaps even easy, to find information about a virus online, purchase the necessary ingredients through the mail, and assemble the components to create a working bioweapon. In this case, the scientists created a synthetic polio virus which was functional enough to kill their test subject, a lab rat. The head of the group, Dr. Eckard Wimmer, noted that his technique implies that even if a virus is eradicated in the wild that it is not gone forever.
Ever since a conversation with my biology teacher in 10th grade I've been convinced that biological weapons are the things we really have to fear. I am not worried about people flying planes into buildings, or even dirty bombs and such. Those kinds of attacks can only kill a few thousand people. But a cleverly engineered biological attack has the potential to affect millions of people, and there are no obvious signs that the attack is underway until it is already too late. I agree with the authors that we need more regulation of the biomedical industry, but it's obvious that even if you tracked and cross referenced every purchase you could never anticipate every malicious intention. As always, it's much easier to stop people from wanting to do something than it is to stop them from doing it. (This story was a Dr. Kahle special.)