Finn Magee combined his industrial design talents with an imagination fermented within apartment walls to come up with what he calls the "Neighbour Rod".
Here, "Neighbor Stick" (as in, 'stick it to your neighbor') seemed a more appropriate moniker.
When the neighbors get noisy, bang on the wall, ceiling, floor with the big white rubber mallet end. When the neighbors get suspiciously quiet, use the stethoscope end.
By the way, that's Betty. She loves to listen.
Finn is one cool dude. More about him, here.