| Ldraw.org: A freeware program which can create Lego models in 3D. Learn about LDraw, download related software and latests parts updates. |
| BlockCAD: 3D fun drawing program uses Lego like blocks. Provides a gallery, downloads, and instructions. |
| LEGO CAD: Simple Machines: A computer-based educational LEGO building kit designed to teach concepts in basic machines. |
| LegoAt.Com: Contains more than 150 lego building instructions with Mlcad files. |
| LeoCAD: A CAD program that uses bricks similar to those found in many toys. The program can import LDraw files. |
| The LDraw model repository: Building instructions for official castle, model team, space, town and train models in LDraw format. |
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