Courtesy of the GDC Vault is this free video of the Game Developers Conference 2011 Game Design Challenge session.
Developers John Romero (Doom, Quake) Jenova Chen (Journey, flOw), and Jason Rohrer (Passage, Sleep is Death) presented to a standing-room only crowd three starkly different approaches to designing games as religions.
Romero simulated Christianity by mixing social media with physical play and requiring the winning apostle to kill Romero himself. Chen gamified the library of TED talks, adding social features to allow people to leave better feedback on how they've been influenced by certain speakers. Rohrer created a "holy object" Minecraft mod that existed on a single USB stick that people could only play in and alter once before passing it on to the next player.
Rohrer's winning concept went on to stir a bit of a holy war, as written by Wired's Jason Fagone, including the USB stick recipient's three month pilgrimage in Hawaii and a frantic online auction for the game.
Session Name: The Game Design Challenge 2011: Bigger than Jesus
Speaker(s): Eric Zimmerman, Jenova Chen, John Romero, Jason Rohrer
Company Name(s): Independent, thatgamecompany, Loot Drop, Independent
Track / Format: Game Design
Video: Designers challenged to make a video game bigger than Jesus
GDC Vault shares for free the Game Design Challenge from GDC 2011, which tasked three developers behind Doom, Journey, and Passage to design games as religions.