LASTools

LASTools is a collection of command line tools to classify, tile, convert, filter, raster, triangulate, contour, clip, and polygonize LiDAR data (to name just a few functions). All of the tools can also be run via a GUI and are available as a LiDAR processing toolbox for ArcGIS versions 9.3, 10.0, and 10.1 of ESRI.