"Guerrilla usability methods" refers to cheap, lightweight usability techniques that can be used to quickly improve the design of a user interface without drawing too much attention to themselves (and therefore don't get shut down). This article, about an L.A. artist's effort to fix a confusing highway sign on an L.A. freeway, takes guerrilla usability to an absolute extreme. I'm in awe.
And I really like Good magazine, the non-technical design publication for people who love design. I get the print version, because the magazine even feels good in one's hands. I've blogged Good before. Highly recommended.