Popular stencils
Free
ELEC AEG
This stencil helped me construct an electrical project for my home.
Free
Rorke storage
Logos and Storage of Rorke
Free
DrayTek Vigor
Vigor 2900G
Free
SADP
Stencils for drawing Self-aligned Double Patterning.
Free
RoboMind graphics
some graphics from robomind (http://www.robomind.net/en/), which is software specifically developed to support technology education. you can now build robomind maps directly in OmniGraffle.
Free
Direct Logic 205: DC IO
Direct Logic 205 DC/IO modules. 9 of 12 stencils.
Free
Direct Logic 205: Analog IO
Direct Logic 205 Analog IO modules. 7 of 12 stencils.
Free
AVM Fritz!Box
AVM Fritz!Box 7390
Free
Si* Notation
This is a stencil for the security extension of the i* requirements in engineering notation.