Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Mathematics
Q&A for people studying math at any level and professionals in related fields
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Photography
Q&A for professional, enthusiast and amateur photographers
Stack Overflow
Q&A for professional and enthusiast programmers
Ask Different
Q&A for power users of Apple hardware and software
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Cross Validated
Q&A for statisticians, data analysts, data miners and data visualization experts
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Personal Finance & Money
Q&A for people who want to be financially literate
Academia
Q&A for academics and those enrolled in higher education
Audio-Video Production
Q&A for engineers, producers, editors, and enthusiasts spanning the fields of audio, video, and media creation
Quantitative Finance
Q&A for finance professionals and academics
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Physics
Q&A for active researchers, academics and students of physics
Signal Processing
Q&A for practitioners of the art and science of signal, image and video processing
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
English Language Learners
Q&A for speakers of other languages learning English
Computer Science
Q&A for students, researchers and practitioners of computer science
Musical Practice & Performance
Q&A for musicians, students, and enthusiasts
Programming Puzzles & Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Personal Productivity
Q&A for people wanting to improve their personal productivity
Physical Fitness
Q&A for physical fitness professionals, athletes, trainers, and those providing health-related needs
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system