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The Mi Yodeya Referencer; a user-script created by HodofHod for quick and easy references to commonly cited seforim on Stack Exchange sites.
For questions about the Winter Bash (or holiday hats) to celebrate the end of the (Gregorian) year.
for questions about suspected user spam, the spam flag or combating spam as a community.
for questions about Mi Yodeya's publication projects in general as opposed to specific projects.