If you ever get caught out needing to validate STL files before committing to rapid prototypes or need to view Pro/E SLP render files, 3D-Tool may help out.
Available from www.3D-Tool.de as a 350Kb download, a thirty day demo offers full viewing and manipulation but not save or export capabilities.
Once loaded parts or assemblies can be viewed shaded or wireframe and be rotated and zoomed including a turntable animation mode.
Sections can also be dragged dynamically through the parts to visualise hidden details.
Alternatively individual part shells can be hidden for clarity.
Dimensions, angle, radius and volume data can be extracted and bitmaps or prints can be generated for design documentation.
The full version costs 51.19 EUR and adds the ability to generate self running executable files for distribution including both the data and a viewer.
These can include a short welcome message for the intended recipient.