Dave Ferguson already called attention to this over on his blog, but I’m going to do it here also.
One of my favorite new-to-me blogs is The Acagamic – Usable Game Science, and it’s marvelous stuff. As a special holiday present, the blog is featuring a series of presentations on things game-y:
As a Christmas special, I will for once update this blog daily for the next 24 days with my favorite presentation slides about games, user experience, game design, emotion, affective and entertainment computing, etc.
The first one is here: http://www.acagamic.com/specials/advent-2009/1-virtual-goods-how-and-why-they-work/
Collect one! Collect them all!