BTW - something you might look up, analogous to "electronic hacking" as you put it - is something called "circuit bending"; typically, it applies to those who perform mods to electronic sound-making toys (like cheap electronic synth keyboards, speak-n-spells, etc); to make them make really weird noises and such. Most of these guys just randomly probe the device, and if they find something that seems "nice" to their ear, they mod it at that point. Rarely do they consult any kind of schematic or diagrams, or even understand what they are doing (the masters of "circuit bending", though - do go to the effort to figure it out; they turn out some interesting stuff).
