Less feature rich, but handy, is a program called aacircuits, for drawing ASCII-art circuit diagrams. It dates way back to the days of Usenet. I still use it to include small schematics in microcontroller source code. For instance if I figure out how to program a particular chip, I include a schematic of a circuit to "demo" the code.

I'd be shocked if aacircuits doesn't run under Wine on a Linux machine.