Mathematics
Q&A for people studying math at any level and professionals in related fields
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Physics
Q&A for active researchers, academics and students of physics
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Cross Validated
Q&A for statisticians, data analysts, data miners and data visualization experts
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
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Signal Processing
Q&A for practitioners of the art and science of signal, image and video processing
Computational Science
Q&A for scientists using computers to solve scientific problems
French Language & Usage
Q&A for students, teachers, and linguists wanting to discuss the finer points of the French language