Architect symbols...

GarageDoors.zip - several roll-up doors
AutoCad version - R14+
file size - 27k

Windows.zip - various types
AutoCad version - R14+
file size - 75k

CabinetHardware.zip
AutoCad version - R14+
file size - 29k

CabinetSections.zip
AutoCad version - R14+
file size - 625k

Landscape symbols...

Tree3d.zip - nice 3D tree
AutoCad version - R14+
file size - 977k

3d-palm.zip - 3D palm tree
AutoCad version - R14+
file size - 53k

Treeplans.zip.-.plans.of.trees.&.shrubs
AutoCad version - R14+
file size - 306k

Miscellaneous...

Automobile.zip
AutoCad version - 2000+
file size - 24k

Watson5.8 by watsonlisp - Artificial intelligence for Autocad. Find detail drawings by text and attribute content. More info at http://geocities.com/watsonlisp

Block Extender
BlockExtender - Free version provides a useful docking dialog box drawing and block explorer. The docking dialog box has two tabs: "Dwgs" and "Blocks".  The "Dwgs" tab allows you to view all of the .dwg files in any directory with their preview bitmap being optionally shown. The "Blocks" tab lists all existing blocks in the current drawing with each block's image that was created using the block or wblock command. Drawings not created using block or wblock will not show a small preview and the block icon is shown instead.
AutoCad version - 2000+
file size - 2.5 meg

heal.zip - turns a broken line into a single line
AutoCad version - R14+
file size - 2k

3dburstr14.zip - 3DBurst is an ARX application which allows the user to quickly create exploded views of 3D models. This command is especially useful in Mechanical design to visualize an engine's inside or in architectural design to separate a building into floors.
AutoCad version - R14
file size - 24k

3dburstr2k.zip - 3DBurst is an ARX application which allows the user to quickly create exploded views of 3D models. This command can be used for instance to visualize an engine's inside or to separate a building into floors. The operation can be performed according to a point, an axis or a plan. The user can also specify a burst factor on which depends the displacement of the selected objects.
AutoCad version - 2000
file size - 26k

3dgear.zip - This program draws 3D solid models of standard involute tooth gears. You can specify the pitch, pressure angle, number of teeth, width, and insertion point. The Precision check box will cause the gear to be created with a more accurate involute and can take more time.
AutoCad version: not specified by contributor
file size - 12k

3dhome.zip - home design program for Windows that creates 3d plans automatically.
AutoCad version: not specified by contributor
file size - 285k

power.zip - Power Tools r2000.00. This package offers you the best tools for AutoCAD 2000 for free. Features include: batch converting to R13, R14, R2000, DXF, DWT, 3DS, WMF with many options; replace blocks with possible use of wildcards; hatch between two lines; disable and enable objects; flatten 3d drawings; plot all views; zoom to object extents; calculate the total area of polylines by layer and many more. Some of these tools have a dialog interface. Help files make this package easy to install and explore. If you are a programmer, feel free to add your routines for the next release.
AutoCad version - 2000
file size - 187k

walldemo.zip - this VBA program takes advantage of Object Oriented Programming. This functions by creating user interfaces to create wall supports. To run this dialog you must load the lisp file in your project and then load the menu file.
AutoCad version: not specified by contributor
file size - 315k

dwg2zip.zip - Dwg2zip is used by architects and engineers all over the world to make AutoCAD drawings ready to share with project participants. The new version 2005 brings new features and improvements to this popular program.

What can Dwg2zip be used for ?
Dwg2zip can bind xrefs and remove frozen and off layers on a group of AutoCAD drawings. Dwg2zip can also convert to previous AutoCAD versions and dxf. Drawing files, drawing lists, fonts, and plotter configuration files can be compressed into a zip file that can be sent by email. The program can also unzip zip files. If a zip file contain drawings, fonts or plotter configuration files then Dwg2zip unzips to the right path on your PC.

Dwg2zip makes sharing drawings easy
Xrefs are a very useful feature with AutoCAD. But to distribute drawings that contain Xrefs is a challenge for many AutoCAD users. Xrefed  drawings must then either be bound to the main drawings, or distributed as separate files. Dwg2zip changes this by automatically binding Xrefs to the main drawings. And the drawings can be cleaned and purged for unwanted layers before distribution. This can be done without any changes made to the original working drawings.
AutoCad version - 2005
file size - 4.8meg