CAD Opensource

1. QCad Community Edition
2. BRL-CAD - constructive solid geometry (csg) modeling
3. Archimedes - architectural design.

Above are links to opensource cad software.

Reduce wifi range

Many people want to improve the range of their wireless network but some people want to reduce it. This morning one guy ask me how to reduce his wifi range at home. My quick answer is hide the router inside a box, table or cupboard.
Changing router mode to 802.11g maybe can decrease the signal range. 802.11N delivers 14x the speed of 802.11G & 6X the range of .11G. One can also applying Wi-Fi blocking paint to block the signal. Read more on anti wifi paint at tech.yahoo.com