VirtuallyShow.com - VirtuallyShow.com is an online affordable and feature-packed virtual tour service that allows you to create your residential and commercial real estate virtual tours in just a minute.
SketchUp - 3D for Everyone
Immoviewer - Immoviewer is a software solution that combines Automated Real-Estate Video Content creation with simple and scalable 3D 360 tours.
Assetforge - Asset Forge allows anyone to create 3D models and 2D sprites using building blocks.
Klapty - Create and share your virtual tours for free or have them done by a professional photographer. Klapty - The world in 360 °.
FreeCAD - An open-source parametric 3D modeler