Many of my best answers are written up fully and ported to my blog. This (along with my other abstract ideas) allows me to create an online portfolio of important and interesting information for both referencing and for others to learn from.
View my LinkedIn Profile.
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
Motor Vehicle Maintenance & Repair
Q&A for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles
Writers
Q&A for authors, editors, reviewers, professional writers, and aspiring writers
Area 51
Stack Exchange Network staging zone, where users come together to build new Q&A sites
Server Fault
Q&A for professional system and network administrators
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Homebrewing
Q&A for dedicated home brewers and serious enthusiasts