University of Oregon Route Views Project
The University's Route Views project was originally conceived as a tool for Internet operators to obtain real-time BGP information about the global routing system from the perspectives of several different backbones and locations around the Internet. Although other tools handle related tasks, such as the various Looking Glass Collections (see e.g. TRACEROUTE.ORG), they typically either provide only a constrained view of the routing system (e.g., either a single provider, or the route server) or they do not provide real-time access to routing data.
While the Route Views project was originally motivated by interest on the part of operators in determining how the global routing system viewed their prefixes and/or AS space, there have been many other interesting uses of this Route Views data. For example, NLANR has used Route Views data for AS path visualization and to study IPv4 address space utilization (archive). Others have used Route Views data to map IP addresses to origin AS for various topological studies. CAIDA has used it in conjunction with the NetGeo database in generating geographic locations for hosts, functionality that both CoralReef and the Skitter project support.