Why is Biology so good at security while computers are so bad?

Anyone that owns a personal computer is painfully aware of the state of computer security today. Viruses, Spyware, Identity Theft, Hackers... the news media is full of reports of the latest security issue to plague society.  It seems that despite incredible advances in computing power, developers are incapable of making a computer that is actually secure.

Drawing from a variety of disciplines including psychology, biology and  computer science, the "big picture" of data used is explored. Using this picture, a better understanding can be gained of the real obstacles to "secure computing". In closing, the promise of biologically-inspired security is examined, and some of the rewards and pitfalls discussed.