FaroScene LT is a free point cloud viewer
Download: http://www.faro.com/faro-3d-app-center/stand-alone-apps/scene-lt

Faro Laser Scan Files, E57, Leica PTZ, PTX, XYZ

• Open Faro Scene LT
• Drag & Drop point cloud file into the window
• If the format is supported, file gets imported into new project
• On the Structure list you can see list of Scans, your file should be listed there
• Right Click over the point cloud item in the list
• Select Import-Export/Export Scan(Ordered)
• Settings: [x] Full Scan and from XYZ tab: Disable [ ] Include row/col *Otherwise it wont work
• Format dropdown: XYZ Ascii Files *.xyz (*this includes RGB data if point cloud contains it)
• Set output file name
• Click Export

Now you can bring that saved .xyz file into your unity project, and use Unity PointCloud viewer & Tools with it

If you want to see the cloud first in FaroSceneLT, then:

• Right Click over the point cloud item in the list
• Select Operations/PointCloudTools/Create Scan PointCloud
• It ask for save changes or create project, save it somewhere
• Click OK in the next dialog (or play with the settings if you want to)
• After finished processing, double click the point cloud filename in Structure list to open 3D viewer