Matt is a huge proponent of WordPress and regularly contributes to the WordPress community. He is the author of several popular themes and plugins, and has made substantial contributions to the official WordPress Codex.
Q&A for professional and enthusiast programmers
Q&A for WordPress developers and administrators
Q&A for power users of Apple hardware and software
Q&A for computer enthusiasts and power users
Q&A for linguists, etymologists, and serious English language enthusiasts
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems.
Q&A for Graphic Design professionals, students, and enthusiasts
Q&A for system and network administrators
Q&A for Ubuntu users and developers