Any of my questions or answers may be used in any project including commercial applications, with no restrictions other than those that Stack Overflow imposes on websites that aggregate their questions and answers.
Q&A for professional and enthusiast programmers
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Q&A for computer enthusiasts and power users
Q&A for passionate videogamers on all platforms
Q&A for linguists, etymologists, and serious English language enthusiasts
Q&A for those who create, solve, and study puzzles