Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Audio-Video Production
Q&A for engineers, producers, editors, and enthusiasts spanning the fields of audio, video, and media creation
Board & Card Games
Q&A for people who like playing board games, designing board games or modifying the rules of existing board games
Musical Practice & Performance
Q&A for musicians, students, and enthusiasts
User Experience
Q&A for user experience researchers and experts
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Server Fault
Q&A for professional system and network administrators
Physics
Q&A for active researchers, academics and students of physics
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Ask Different
Q&A for power users of Apple hardware and software
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Game Development
Q&A for professional and independent game developers
Mathematics
Q&A for people studying math at any level and professionals in related fields
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Martial Arts
Q&A for students and teachers of all martial arts
Writers
Q&A for authors, editors, reviewers, professional writers, and aspiring writers