Open source system diagramming?

I'm trying to track down an open source layout tool that allows you to place larger components like an arduino, etc. into a general system diagram.

This tools is would be the macro equivalent to Eagle or a schematic and circuit layout tool.

I believe that it was based in Java like the Arduino IDE.

Have you seen Fritzing? http://fritzing.org/

yes! that's the one I was looking for.

Thanks Much,

Rob