I'm developing https://www.talkyard.io, which is a bit like open source StackOverflow, and also supports open-ended discussons, chat, and embedded comments.
All original source snippets that I post on StackOverflow and StackExchange sites are licensed under Creative Common's CC0 (in addition to the license prescribed by StackOverflow.)
Contact: kajmagnus3 at gmail ...
Stack Overflow
Q&A for professional and enthusiast programmers
Database Administrators
Q&A for database professionals who wish to improve their database skills and learn from others in the community
Information Security
Q&A for information security professionals
Server Fault
Q&A for system and network administrators
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
WordPress Development
Q&A for WordPress developers and administrators
Super User
Q&A for computer enthusiasts and power users
User Experience
Q&A for user experience researchers and experts
Ask Ubuntu
Q&A for Ubuntu users and developers
Software Recommendations
Q&A for people seeking specific software recommendations
Code Review
Q&A for peer programmer code reviews
Area 51
Q&A for proposing new sites in the Stack Exchange network
Open Source
Q&A for people organizing, marketing or licensing open source development projects
English Language Learners
Q&A for speakers of other languages learning English
Parenting
Q&A for parents, grandparents, nannies and others with a parenting role
Graphic Design
Q&A for Graphic Design professionals, students, and enthusiasts
Network Engineering
Q&A for network engineers
Software Quality Assurance & Testing
Q&A for software quality control experts, automation engineers, and software testers
Politics
Q&A for people interested in governments, policies, and political processes
The Workplace
Q&A for members of the workforce navigating the professional setting
Bitcoin
Q&A for Bitcoin users, developers, and enthusiasts
Cryptography
Q&A for software developers, mathematicians and others interested in cryptography
Unix & Linux
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems
Music: Practice & Theory
Q&A for musicians, students, and enthusiasts
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Travel
Q&A for road warriors and seasoned travelers
Web Applications
Q&A for power users of web applications
Freelancing
Q&A for self-employed and freelance workers
Mathematics
Q&A for people studying math at any level and professionals in related fields
Android Enthusiasts
Q&A for enthusiasts and power users of the Android operating system
English Language & Usage
Q&A for linguists, etymologists, and serious English language enthusiasts
Cross Validated
Q&A for people interested in statistics, machine learning, data analysis, data mining, and data visualization
Interpersonal Skills
Q&A for people looking to improve their interpersonal communication skills