McAnnaly's pub is actually a good example also.
Harry made a charm specifically to disperse his output so he could have that on-camera interview at the talk show. That was back when such things were really somewhat beyond his skill and understanding.
A similar device with traits similar to those of Mac's pub, such as thirteen star-shaped studs with thirteen points, etc..might make it a viable flow disruptor and diverter. Less like a ward and more like a veil...except instead of cloaking it from sight, you're sending magic AROUND it, instead of through it.
Also, wards can be set to allow the passage of certain objects or concepts. Hence why Harry's friends have charms that will allow them past his wards without having to disarm them. Someone without a charm tries to go through, even if they're just following Murph...kablooie. It wouldn't be a far stretch I think to design a ward around something like a dvd-player that requires only limited interaction anyway. Perhaps carve the charm into the bottom of the disc tray so that the user doesn't have to cross into it...therefore never breaking it. Using a computer would be much more complicated, but still doable in a similar concept, I think.
Also, advanced electronics are only vulnerable while powered...as long as any battery is removed or they're completely unplugged, wizards can't hex them, even on purpose. They have to be doing something, even if it's just passive current flow.