Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Server Fault
Q&A for professional system and network administrators
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Mathematics
Q&A for people studying math at any level and professionals in related fields
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Cross Validated
Q&A for statisticians, data analysts, data miners and data visualization experts
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
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.
Physics
Q&A for active researchers, academics and students of physics
WordPress Answers
Q&A for WordPress developers and administrators
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Photography
Q&A for professional, enthusiast and amateur photographers
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Ask Different
Q&A for power users of Apple hardware and software
Bicycles
Q&A for people who build and repair bicycles, people who train cycling, or commute on bicycles
Stack Apps
Q&A for apps, scripts, and development with the Stack Exchange API
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
User Experience
Q&A for user experience researchers and experts
Mi Yodeya
Q&A for those who base their lives on Jewish law and tradition and anyone interested in learning more
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Game Development
Q&A for professional and independent game developers
English Language Learners
Q&A for speakers of other languages learning English
Parenting
Q&A for parents, grandparents, nannies and others with a parenting role
Musical Practice & Performance
Q&A for musicians, students, and enthusiasts
Audio-Video Production
Q&A for engineers, producers, editors, and enthusiasts spanning the fields of audio, video, and media creation
Software Quality Assurance & Testing
Q&A for software quality control experts, automation engineers, and software testers
Programming Puzzles & Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Islam
Q&A for Muslims, experts in Islam, and those interested in learning more about Islam
Computer Science
Q&A for students, researchers and practitioners of computer science
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Quantitative Finance
Q&A for finance professionals and academics
Motor Vehicle Maintenance & Repair
Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
Graphic Design
Q&A for professional graphic designers and non-designers trying to do their own graphic design
Answers OnStartups
Q&A for entrepreneurs looking to start or run a new business
Board & Card Games
Q&A for people who like playing board games, designing board games or modifying the rules of existing board games
Homebrewing
Q&A for dedicated home brewers and serious enthusiasts
German Language & Usage
Q&A for speakers of German wanting to discuss the finer points of the language and translation
Personal Finance & Money
Q&A for people who want to be financially literate
Writers
Q&A for authors, editors, reviewers, professional writers, and aspiring writers
Japanese Language & Usage
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Japanese language