Everybody hates spam. Everybody hates HIV. So the fact that Microsoft is sharing its knowledge of spam filter design to help scientists fight the virus is all kinds of good.

Miscrosoft Research have teamed up with the Ragon Institute — a collaboration between MIT, Harvard, and Massachusetts General Hospital which is dedicated to finding an HIV/AIDS vaccine that actually works.

But what has spam got to do with it? Well, it turns out that HIV mutates over time in a way that is analogous to the way email spammers change their tactics to beat filters. The HIV virus is always looking for a different way to beat the human immune system, which is the exact same problem faced by anyone keen to block spam.

So Microsoft have stepped in to help the Ragon Institute by re-purposing the tools they use to filter out spam in Hotmail and Outlook to predict likely HIV mutations. They've already developed an application called PhyloD which crunches through the massive amount of data coming out of the Ragon Institute.

In fact, with PhyloD, Microsoft were able to process a year's worth of data over a weekend explains Microsoft's David Heckerman:

"[Ragon director Bruce Walker] had this great data set but he didn't know how to analyze it. We happened to have just the right algorithm for it and this large bank of computers at Microsoft that could do this massive amount of computation. He gave us the problem on Friday. On Monday, we had a completed analysis for him."

The result? The discovery of six times as many possible attack points on the HIV virus than had been identified in the past. [Microsoft Research via Threat Post]