Tier City
Kyn Lafortune
Alchemist's Truth (1)
Strata
Terry Pratchett
The Roads Must Roll
Robert A. Heinlein
Future History or "Heinlein Timeline" (3)
The Secret History of Mac Gaming
Richard Moss
Half-Real: Video Games between Real Rules and Fictional Worlds
Jesper Juul
The Warcraft Civilization: Social Science in a Virtual World
William Sims Bainbridge