This series of screen shots shows the classifications tools from Trimble RealWorks 10. The top image shows a noisy data set containing vehicles at an intersection along with some buildings and a lot of trees.
The next image shows the results of the fully automatic classification which took about 20 minutes to process. Notice how clean the road is!
The last image shows the final results after manually classifying objects improperly identified by the automated tools. This took about 5 minutes.
The result is a much more manageable point cloud to begin working with.