Siemens PLM Software distributes Solid Edge 2D Drafting ST for free to promote their middle end 3D product Solid Edge. This is not an evaluation version or beta version, it is a full function commercial software. Solid Edge 2D Drafting ST is compatible with AutoCAD DWG format. I have tested some files in AutoCAD2006 format, it works fine. It could be a low cost alternative for small business.

Free 2D: PLM