David Heckerman, the guy who invented Microsoft's email spam filter, is now fighting another type of invader: HIV. The two are similar in that they constantly mutate, explains Heckerman, a scientist with Microsoft Research who is collaborating with the Ragon Institute. To create strong spam filters, scientists must crunch enormous amounts of data about spam. Similarly, researchers are cataloguing huge databases of HIV, looking for fragments where the virus is vulnerable to attack. They've narrowed it down to about 20 areas, and that's where scientists like Ragon's Marcus Altfeld begin their work in the lab, hoping to one day delete HIV like so much annoying email.