The Grey Goo website now offers Grey Goo: Emergence, a DLC pack that's free for all owners of Petroglyph's RTS game for a limited time, as the offer ends tomorrow at noon EDT, when picking this up will require cash money. Here's word:

This 3 mission, Grey Goo mini-campaign follows the events of Singleton immediately following the explosion at the Terminal, and reveals the true motivations behind the overwhelming Goo force.

An ally turned enemy, Singleton’s journey remains a mystery to his former companions. But what happened to cause his corruption and turn? And what drives the Goo itself? Delve into the Goo's origins and learn its true intention and plan for the galaxy.