Do you draw your schemes and designs in the secret free "CAD" application by Autodesk?
This was inspired by the Autodesk's secret free design application blog post on the RobiNZ CAD Blog.
The review and markup tools in Autodesk Design Review are quite powerful. Powerful enough to be used as a standalone drawing application for simple schemes. As the Autodesk Design Review application is free, you can easily use these "CAD-like" tools anywhere you want. Just download it from www.autodesk.com
In Design Review, you get a toolset of simple shapes, texts, polylines, freehand drawing, dimensioning tools (length, area, angle), color selection (line+fill), transparency settings, grip editing, symbol libraries, advanced plotting tools and more. The file format for this "CAD" software is of course DWF and DWFx. With DWFx you can view your drawings natively, without any viewer in Windows Vista, or Windows XP with MSIE7.
Some of the CAD functions in Design Review are not available even in the big AutoCAD. E.g. you have access to the history of the individual entities - you can see who and when has created each line.
To start quickly with a blank canvas (which is not a native option in this markup application), you can use the Empty-sheet DWFx file from the CAD Block Catalog. Just open it in Design Review 2009 and start to draw...
The user interface for drawing is much nicer in the upcoming Design Review 2010, currently in beta