Other examples of open data projects gathering information in specific domains: OpenAerialMap http://openaerialmap.org compiles remote and satellite imagery, as well as open tools for manipulating aerial photographs that can be used to quickly create up-to-date, high-resolution, and free images. OpenCellID http://www.opencellid.org and WiGLE http://wigle.net are two databases that gather cell-tower locations and Wi-Fi locations to create geolocation tools. They serve as crowd-sourced alternatives to Skyhook Wireless's geo-located Wi-Fi database. Navizon http://navizon.com is trying out various ways to encourage people to contribute to its geoloca- tion database, among them monetary payments and credits that can be redeemed for querying the Navizon database. OpenStreetMap and other communities have built private and merged into qualified data sets or packaged and sold. User-generated data is compelling because it offers data where none currently exists. By harnessing the collective power of distributed customers, companies can gather information of value to those same customers. Projects like OpenStreetMap demonstrate that users will contribute geographic data when they need it and it is unavailable. By providing tools and a community, these projects leverage individual users to create and maintain quality datasets. Emergence of Online Geographic Data: GeoWeb Much as the Web opened up with users sharing infor- mation via text and images, the GeoWeb has emerged as easy-to-use publishing and hosting tools, open data formats, and widely available fast connectivity--making sharing geodata and community building possible.