Super User
Q&A for computer enthusiasts and power users
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Stack Overflow
Q&A for professional and enthusiast programmers
Area 51
Q&A for proposing new sites in the Stack Exchange network
Skeptics
Q&A for scientific skepticism
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Ask Different
Q&A for power users of Apple hardware and software
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
English Language Learners
Q&A for speakers of other languages learning English
Arqade
Q&A for passionate videogamers on all platforms
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Software Quality Assurance & Testing
Q&A for software quality control experts, automation engineers, and software testers
German Language
Q&A for speakers of German wanting to discuss the finer points of the language and translation
Bitcoin
Q&A for Bitcoin users, developers, and enthusiasts
Linguistics
Q&A for professional linguists and others with an interest in linguistic research and theory
French Language
Q&A for students, teachers, and linguists wanting to discuss the finer points of the French language
Raspberry Pi
Q&A for users and developers of hardware and software for Raspberry Pi
Politics
Q&A for people interested in governments, policies, and political processes
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Japanese Language
Q&A for students, teachers, and linguists wanting to discuss the finer points of the Japanese language
Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Web Applications
Q&A for power users of web applications
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Writing
Q&A for the craft of professional writing, including fiction, non-fiction, technical, scholarly, and commercial writing
Physics
Q&A for active researchers, academics and students of physics
Bicycles
Q&A for people who build and repair bicycles, people who train cycling, or commute on bicycles
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Server Fault
Q&A for system and network administrators
Ask Ubuntu
Q&A for Ubuntu users and developers
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Mathematics
Q&A for people studying math at any level and professionals in related fields
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Photography
Q&A for professional, enthusiast and amateur photographers
Code Review
Q&A for peer programmer code reviews
Information Security
Q&A for information security professionals