Stack Overflow
Q&A for professional and enthusiast programmers
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Musical Practice & Performance
Q&A for musicians, students, and enthusiasts
Server Fault
Q&A for professional system and network administrators
Audio-Video Production
Q&A for engineers, producers, editors, and enthusiasts spanning the fields of audio, video, and media creation
Geographic Information Systems
Q&A for cartographers, geographers and GIS professionals
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Photography
Q&A for professional, enthusiast and amateur photographers
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Physics
Q&A for active researchers, academics and students of physics
User Experience
Q&A for user experience researchers and experts
Personal Finance & Money
Q&A for people who want to be financially literate
Signal Processing
Q&A for practitioners of the art and science of signal, image and video processing
Genealogy & Family History
Q&A for expert genealogists and people interested in genealogy or family history