NanoCAD is a 
Java applet (formerly a 
Scheme program) that was intended to eventually evolve into a useful computer-aided design system for 
nanotechnology. While that goal has yet to come to fruition, NanoCAD has at least influenced the direction of more advanced projects such as 
OpenChem[?] and 
Fungimol.
The NanoCAD Java applet is available to tinker with at http://willware.net:8080/ncad
 
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