OpenTopography provides high-quality geographic data relating to earth science as well as a platform for researchers to share their own data. Based at the University of California, San Diego, OpenTopography is an ambitious project that "facilitates community access to high-resolution, Earth science-oriented, topography data, and related tools and resources," and is funded through the National Science Foundation. Visitors can search or browse the project's more than 300 datasets (as of this write-up) via an interactive data map and a data catalog, both found under Data. Most of these datasets are available in Lidar point cloud format, and many are also available in other formats, such as raster or Google Earth. Visitors should also check out the Tools section, where they will find descriptions of the tools OpenTopography uses to enable on-demand processing, analysis, and visualization of their datasets. This section also contains their Tool Registry, which they describe as "a community populated clearinghouse of software, utilities, and tools oriented towards high-resolution topography data," as well as OpenTopography's open-source software. For new users, the Getting Started page (linked at the upper left) provides a helpful orientation to the site, and there are also several tutorials on Lidar available under Learn.