IBM's City Forward just launched and it's a wonderful free resource for aggregating data about cities all over the world. Using data from publicly available resources (e.g. U.S. Census Bureau, Australia Bureau of Statistics, EuroStat, UK National Statistics, etc.), City Forward allows users to "gain insight into urban issues such as transportation, energy, health, education and the environment." Using the data provided, users create "explorations" showing patterns and correlations within that data. Starting from their explorations tab, users enter the city or cities they want to explore combined with subjects of interest like transportation or health and then choose how they'd like to see the data presented. There are several explorations already created and even a community page to discuss explorations or provide troubleshooting. Check out the video below to see City Forward in action.