The CloudView project is a proof-of-concept WebGL LAS viewer. The original purpose of the project was to be the viewer for the processed point clouds generated by CloudAE. CloudAE is still tailored for processing airborne LiDAR, so this is not the best general purpose viewer for terrestrial LiDAR or 3D models. For more general-purpose projects, check out Markus Schütz's Potree and Oliver Kreylos' Lidar Visualization.
Try out the demo.