Visio can do electrical diagrams also, but it's to expensive and complicated for just electrical things i think.
Microsoft Visio - Starting at $199
SmartDraw - Starting at $69
Crocodile Clips (now called Crocodile Physics) starting at about $350 to $400
Crocodile Physics has a 1-5 users license, which is aimed at schools. You may be able to find an older version of Crocodile Clips cheaper or even free perhaps. Or get it in a less legal way.
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