Without wishing to sound too pompous about it, I really believe that we all have to do our bit to reduce the perceived nuisance of light aircraft over built up areas - it's in all of our long term interests after all.
That for me extends to refusing to buy photos of my house, even if they are good - I dont wish to encourage these guys from exacerbating the bad image that we are already tarred with in light aviation.
I also try to take into account my noise nuisance potential when I'm cruising around locally - I restrict circling over locations to no more than one 360 turn in each direction, and I try to stay at 1500 AGL minimum (but always able to glide to open land)- this isnt too easy to judge sometimes as the ground in our local flying area gets progressively higher as you fly out from the airfield.
Furthermore, if heading out to the local flying areas, I try to look for the routes that arent necessarily on a direct track, (the one that everyone uses of course) but for a route crossing areas which are less densely populated.
Another one to watch for in terms of alerting the local populace is sudden changes in engine note - guaranteed to get heads turning, and some of our locals have complained about us "stalling our engines" and "aerobatics" over their houses
When over the towns and villages or when on base I try to progressively change the settings rather than suddenly.
I believe someone has recently been prosecuted for low flying up in Lancashire recently - but I havent read any official reports so I dont know the circumstances.
h