DWGFREE - DWGFREE is an online platform that comes with a comprehensive collection of CAD blocks that can be downloaded without the need for registration.
A360 VIEWER - Free online CAD Viewer
CADMAPPER - Instant CAD files for any location on earth
STP Viewer - Free STP Viewer - free software that lets you view 3D STEP files (.stp, .step file format).
MAPACAD - MAPACAD is an online website that is providing leverage to designers and architectures to have the ability to download CAD map cities that can be directly used in their projects.
Glovius - Extensible & customizable 3D viewer, for consumption of product design data.