Photo via timschreier's flickr

This makes so much sense now: the phrase "wait for the other shoe to drop" was born from noisy New York City neighbors:

"A common experience of tenement living and other similar style housing in New York City during the manufacturing boom of the late 19th and early 20th century. Apartments were built similar in design with one's bedroom under another's. Thus, it was normal to hear a neighbor removing shoes and hearing them hit the floor above. As one shoe made a sound hitting the floor, the expectation for the other shoe to make a similar sound was created."

The unsteady pattern of neighbor noise is maddening still, but in modern times it's more like: waiting for the other bass to drop, waiting for the other random piece of furniture to be moved around endlessly, waiting for the television to be turned off, waiting for that winning lottery ticket so I can move to a palace with no neighbors, and so on. At least we have white noise machines now. [via Reddit]