I know it is an old post, I found it whilst searching for something else... however, one big, BIGGGGG point of legality and liability comes to mind:
If you remove the company fuse, then alcoholic/druggy neighbour comes out to have a look at it, then you are likely to be held liable when he kills himself touching the exposed live conductors. Now, he is obviously a complete <
manual manipulator of male genitalia>, but is he really worth risking a spell in prison and a criminal record for? So whatever you do, do not do this!
As to the other options
1) EMP generator: not a good idea. I haven't seen any of these internet designs, but I suspect you would not have any luck with them. They are probably verbatim copies of the stuff we used to read in "The Jolly Roger's Cookbook"

In order to have the desired effect you need BIG power. You would need to build a pretty formidable capacitor bank, and also as you have identified, would be at a real danger of frazzling your own equipment. A stereo system is not particularly sophisticated and your computer would be long gone before the stereo! It would be cheaper to pay a solicitor to do what is necessary to get him shut-up
2) Find out if he rents or owns the place. If he rents, the landlord
might be interested. There was a post recently on how to find out the names and contact details of landlords (I think it was by RichardP, if memory serves correct)
3)
Avoid getting him an ASBO if possible. It is likely that when selling, "the neighbour has an ASBO" is even worse than "we have a minor dispute with the neighbour". Unfortunately this sort of thing has the effect of penalising the innocent party, as it is harder to sell a house with this sort of stigma.
Unfortunately these antisocial gets are hard to get to cooperate. I tried to help some friends who were having problems with their scary all-night loud neighbours: the nearest we got to cooperation was that they invited us to their dodgy parties

Not sure your mother would be too keen on "hang out with the wino/druggy neighbour" as a solution to this though.
However, here comes 4:
4) If he IS a druggy, and you are CERTAIN of this, then there is nothing stopping you from tipping off the police. Last time I checked "Has the neighbouring property ever been used as a crack den?" is not a question buyers ask. If he smokes a bit of pot then don't bother, nothing will come of it. But if you think he is using class A stuff in there, especially if he seems to do it in large gatherings, then the police will take it more seriously (although if you want them marched off to prison then don't hold your breath!). A few instances of this and he may grow weary of the police attention.
In the meantime, just try to get those powerless morons at the council to do something.