have they got a dog?
if they have, next time they go out, feed it a ton of ex lax or the like through the letterbox.
won't make 'em quiet, but you will have a good laugh at the noise when they get home...
seroiusly, I sympathise with you. had a bad neighbour, and they can make your life hell.
keep trying to be nice about it if there's hope to resolve it amicably, but if that fails...........
after many months of being "pc" about it and having it thrown in my face, I waited until they went on holiday, and poured a gallon of milk and raw egg through their letterbox...............
