The pages of numbers, however, are not nearly as convincing as seeing the tower self-destruct. I've lately been fascinated by programs that simulate electronic circuits. They let you build analog or digital circuits, then watch them run. You might think that watching a circuit run is right up there with watching a refrigerator put the chill on a carton of milk, but this isn't the case at all. You control the settings of adjustable components from your keyboard, and things happen on the screen.
Lights wink on and off, digital displays flash.
Analog circuits show you their frequency response and attenuation. Digital circuits behave according to the principles of Boolean logic, with the additional real-world effects of propagation delays and device loading. I tested both of these programs over the past couple of weeks, and I'd be hard-pressed to choose between them. But CircuitMaker allows you to mirror parts as well as rotate them. Both programs could benefit from tear-off menus, so that users could choose the tools that they need rather than repeatedly burrowing through menus.