I'm usually of the view of live and let live when it comes to neighbours. We have 2 young kids so I'm aware we make a fair bit of noise, and I'm fairly tolerant of other neighbours noise DH is a different matter but I usually talk him round
We have people living behind us who appear to have no consideration for other people at all, and it seems to be steadily getting worse (or maybe our patience is getting thinner)
Loud music at all times of the day and night, playing drums in an open garage, parties that go on late, revving car and boat engines. It's pretty much every weekend now and will only get worse as the weather improves (nearly summer here).
DH has taken to sleeping on the living room floor on bad nights as their balcony is right by our bedroom window. I can hear the noise come through DD2's baby monitor. She frequently wakes when they are making noise, but she's such a bad sleeper that it's hard to know what causes her to wake.
It's now nearly half past midnight here and they appear to have finally quietened down. They are frequently later than this, but rarely quietened down earlier.
We called out once to them (relatively politely, at nearly midnight) asking if they could keep the noise down and were met with a stream of abuse (admittedly we don't know if it was them or some of their guests) and I've heard the same directed at other neighbours.
It feels really petty, but I'm very tempted to make a noise complaint. WIBtotallyU? Or should we just put up with it (and just put something in DH's tea to chill him out a bit 
). I really don't fancy the quiet word approach after the stream of abuse we got last time.