Studio Designer - Studio Designer is totally different from the traditional designing and home decorating programs.
Floorplanner - Floor plan interior design software. Design your house, home, room, apartment, kitchen, bathroom, bedroom, office or classroom online for free or sell real estate better with interactive 2D and 3D floorplans.
Design Manager - Design Manager is an interior designing software that is designed by the leading project management and architecture groups of the world.
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.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
SketchUp - 3D for Everyone