‘Tis the season for developers’ calendars

Christmas is upon us. Developers are embracing the spirit of sharing their knowledge and wisdom, while taking the opportunity to look back and recollect what 2010 brought us in terms of new technologies and ideas.

A number of "advent" calendars started posting their blog-a-day-till-Dec-24th. Here are some for your reading pleasure while you kick back with a glass of wine by the fireplace:

24 Ways Advent Calendarcalendar-24ways
24 ways (to impress your friends) started back in 2005. It focuses on web design, as well as development topics.
PHP Advent Calendarcalendar-php
PHP advent is the same but for PHP-related topics (psst, the archives are here: 2009, 2009).
Perl Advent Calendarcalendar-perl
Perl Advent goes way back, to the distant Y2K.
Web Performance Advent Calendarcalendar-performance
The Web Performance Calendar, started by yours truly last year, is coming back for another go — this time with many more contributors from companies like Google, Facebook, and Yahoo's own Nicholas Zakas, Mark Nottingham, Philip Telis, and Marcel Duran.
HTML5 Advent(ure) Calendarcalendar-html5
HTML5 Advent is the newest kid on the block. It doesn't have the usual article-a-day, but "24 days of killer demos, tutorials, community buzz..."
Any calendars I missed? Please add them via comments.