Roomtodo - Simple yet powerful online tool for interior design and floorplans with built in walkthrough module.
SketchUp - 3D for Everyone
Sweet Home 3D - Sweet Home 3D is a free interior design application that helps to draw the plan of house, arrange furniture on it and visit the results in 3D.
ArchiCAD - ArchiCAD 16 enables BIM modeling with a new green approach to planning. Create anything you need with ArchiCAD's flexible new features for design.
Palette CAD - Palette CAD is one of the easiest 3D design software for those people who want to use a simple to use program for interior designs.
e-Builder - e-Builder is a construction program management solution that manages capital program cost, schedule, and documents.