Up until about release 11 or 12, Autiodesk produced a native Unix version of AutoCAD.
I have tried some of the intelliCAD based programs on Windows and was very impressed. I have not been able to get one to work on Ubuntu yet, hopefully I will when I get more time. I downloaded the BricsCAD linux trial as a RPM an converted it to DEB with alien and it installed fine. Problem is, I couldn't run it. It would not accept my authorization code for the free trial. It semmed like an issue with root on Ubuntu.
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