00Here are some links to download Interior Design related software for FREE. Have never tried it before, perhaps will try when I got a new house to design ;p
Note: Some of the sites are in Chinese.
1. www.homekoo.com/myhome_diy/software_index.php
2. www.72xuan.com/download
3. http://diy.e-jjj.com/softdown.asp
4. http://www.floorplanner.com/
5. www.sweethome3d.com/download.jsp
6. sketchup.google.com/download/