Axcad is a DWG file compatible and AutoCAD command compatible CAD, it is another affordable choice for ex AutoCAD users. Using dwg as native file formate, supports AutoCAD 2007 dwg format. Site license is availabel, good for Citrix
STL2CAD 2007 - Import STL is an AutoCAD 2007, 2008 and 2009 application to import STL files (Stereo Lithography) into AutoCAD drawing. It can import STL file and create lines, points, faces, polyface mesh and 3d solid drawing entities.
IGES Import for AutoCAD is an IGES file import plug-in for AutoCAD?® and allows you to import GES model into AutoCAD?® for modeling or drafting in 2D/3D.