Incorrect destruction of an IC2 machine (through either explosions, mining, or wrenching fails) produces a Machine Block in addition to a Damaged Circuitry item, which has a ScrapBox mechanic in that it can be right-clicked for the chance to produce several components of an Electrical Circuit.
Suggested in an effort to reduce bug reports on wrenching fails, as well as help illustrate the concept that the machine was damaged when you deconstructed it.
Edit:
Adding Noert's suggestion: Make the Damaged Circuitry able to be repaired with Redstone and Copper wires via a recipe. I also add, since we're going down this route, an Damaged Advance Circuitry that does the same thing, except for advanced machines (And a higher chance for goodies/higher repair cost).