The Great Connection
From Halopedia, the Halo wiki
The fourth episode began with a strange equation from the third server, and a strange poem was posted onto Halo3.com by a mysterious entity called "When We Two Parted". This poem was modified to read "CASTAWAYTHEORYVOLMAN" which lead users to find a book named The Castaway Theory with the equation matching the one from the third server. In the books forums, a close friend of the author indicated that the author went missing awhile back, and over the next several days the friend indicated the author had returned and gave a way for people to talk to him. This lead the author to link to the forth server. The fourth server went over the Conservation Measure and wondered the question on where the Flood came from.
Server 4 opens at Halo3.com on August 9. Many strange things are found, such as hidden buttons, and "light halos" around certain buttons as well.