Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
TeX - LaTeX
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Christianity
Q&A for committed Christians, experts in Christianity and those interested in learning more
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Game Development
Q&A for professional and independent game developers
Server Fault
Q&A for professional system and network administrators
Physics
Q&A for active researchers, academics and students of physics
Programmers
Q&A for professional programmers interested in conceptual questions about software development
Meta Stack Overflow
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Cognitive Sciences
Q&A for practitioners, researchers, and students in cognitive science, psychology, neuroscience, and psychiatry
German Language & Usage
Q&A for speakers of German wanting to discuss the finer points of the language and translation
Mathematics
Q&A for people studying math at any level and professionals in related fields
