@idea from Christian
We know about shouting, of course, but what about other ways? Knocking for doors is good and already implemented, but how about shaking and rattling chain-link fences to try and alert someone in the opposite room to your presence (but not alert say, the whole neighborhood)? Firing guns into the sky is another good idea that has been mentioned elsewhere, but would probably take more time to implement (and I believe is already on 'the list'). Just shooting out ideas here. Any comments or other ideas?
