CADalytic Media has released a free beta of SpecifiCAD for ArchiCAD 10/11, AutoCAD, ADT, Revit and Sketchup. SpecifiCAD allows you to click on a building component within each of these programs and access its CAD details, 3D models, specifications and Green information using the Sweets Catalog network and the Sketchup 3D warehouse depositories.
Download SpecifiCAD from [...]

This Czech site (don’t worry, the link is for the English page) contains some useful software, routines, patches and fonts for AutoDesk related products. New uploads have their date highlighted in red so even if you check it once in a couple of months, it’s easy to see what’s changed.
XANADU - CAD files and utilities

This is an interactive 3D object editor that works within ArchiCAD to define and modify geometrical objects. Don’t forget to also download the toolbox manual which is twice the size of the software itself.
Archi-data Ltd. - GDL Toolbox
Edit: The link above no longer works. See the new post on the subject: gdl toolbox only in [...]

Arexline are distributing two free plugins for Archicad. rxDuplicator allows you to place copies of a selected element along any path, whether straight, curved or splined. rxAutoMaterials helps you create material parameters for GDL objects.
http://www.arexline.com

Here’s some freeware that will make it easier to sort and find drawing files in Windows Explorer. DWGcolumn which can list files by the version of AutoCAD in which it was saved is extremely useful. The screenshots on the site make the use of each utility quite clear.
http://www.cushat.co.uk/fw/

If you’re using a slightly old version of AutoCAD, you’ll find yourself cursing those who send you drawings in the latest format because they won’t open properly on your system. Clean up your language - DwgGateway is here to help. It can open and save-as from and to just about any version of *.dwg files.
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