Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Personal Productivity
Q&A for people wanting to improve their personal productivity
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
French Language & Usage
Q&A for students, teachers, and linguists wanting to discuss the finer points of the French language
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Photography
Q&A for professional, enthusiast and amateur photographers
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Physics
Q&A for active researchers, academics and students of physics
Game Development
Q&A for professional and independent game developers
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
Server Fault
Q&A for professional system and network administrators
Mathematics
Q&A for people studying math at any level and professionals in related fields
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Cross Validated
Q&A for statisticians, data analysts, data miners and data visualization experts
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Board & Card Games
Q&A for people who like playing board games, designing board games or modifying the rules of existing board games
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Chess
Q&A for serious players and enthusiasts of chess
Computer Science
Q&A for students, researchers and practitioners of computer science
Programming Puzzles & Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Academia
Q&A for academics and those enrolled in higher education