Worldbuilding
Q&A for writers/artists using science, geography and culture to construct imaginary worlds and settings
Stack Overflow
Q&A for professional and enthusiast programmers
Computer Science
Q&A for students, researchers and practitioners of computer science
Chemistry
Q&A for scientists, academics, teachers, and students in the field of chemistry
Mathematics
Q&A for people studying math at any level and professionals in related fields
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Earth Science
Q&A for those interested in the geology, meteorology, oceanography, and environmental sciences
Astronomy
Q&A for astronomers and astrophysicists
Biology
Q&A for biology researchers, academics, and students
Super User
Q&A for computer enthusiasts and power users
Seasoned Advice
Q&A for professional and amateur chefs
Chess
Q&A for serious players and enthusiasts of chess