Cyburbia calls itself an "urban planning portal," a resource for urban design students, professionals, and self-described "planning geeks." Since that last phrase definitely describes many of us here at WorldChanging, Cyburbia is a worthy addition to the worldchanger's bookmark list. I expect to be returning to it often.
Cyburbia is a classic web portal -- it indexes and links to thousands of planning and urbanism-related websites organized by subject matter and focus. The site also houses active web forums on urban planning, as well as photo galleries of both the best and the worst in city design. While sustainability and sustainable urban design are not the focus of Cyburbia, they are part of the bigger picture embraced by Cyburbia.