Super User
Q&A for computer enthusiasts and power users
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
Aviation
Q&A for aircraft pilots, mechanics, and enthusiasts
Stack Overflow
Q&A for professional and enthusiast programmers
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
The Workplace
Q&A for members of the workforce navigating the professional setting
Robotics
Q&A for professional robotic engineers, hobbyists, researchers and students
Personal Finance & Money
Q&A for people who want to be financially literate
Vi and Vim
Q&A for people using the vi and Vim families of text editors
Motor Vehicle Maintenance & Repair
Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
Software Recommendations
Q&A for people seeking specific software recommendations
Mathematics
Q&A for people studying math at any level and professionals in related fields
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Worldbuilding
Q&A for writers/artists using science, geography and culture to construct imaginary worlds and settings
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Ask Ubuntu
Q&A for Ubuntu users and developers
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Information Security
Q&A for information security professionals
Artificial Intelligence
Q&A for people interested in conceptual questions about life and challenges in a world where "cognitive" functions can be mimicked in purely digital environment
Signal Processing
Q&A for practitioners of the art and science of signal, image and video processing
Academia
Q&A for academics and those enrolled in higher education
Space Exploration
Q&A for spacecraft operators, scientists, engineers, and enthusiasts
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Bicycles
Q&A for people who build and repair bicycles, people who train cycling, or commute on bicycles
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Web Applications
Q&A for power users of web applications
The Great Outdoors
Q&A for people who love being outdoors enjoying nature and wilderness, and learning about the required skills and equipment
Computer Science
Q&A for students, researchers and practitioners of computer science
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Ask Different
Q&A for power users of Apple hardware and software