Early game I produced using a scale 3D model of a Drivable Conostoga Wagon (rigged with physics) in multiple game engines:
- Sketchup, using the plugin Sketchy Physics (stopped using Sketchup after Google sold them to Trimble and went paid/web)
- 3D RAD, a low level game engine – owner closed shop, community rallied and rebuilt engine, owner gave source to community
- Unity 3, yes this was a while back.
This was a great project that allowed me to get a good review of what software had to offer at the time, their physics capabilities, and how the communities operated.