"It was a day like any other."

[Jonathan Lighter]

Possibly second only to "It was a dark and stormy night" as an ominous
cliche, and certainly far more ironic.

The earliest use I can discover - in the more or less ominous sense:

1914 Ernst von Wolzogen (trans. Edward Breck & Charles Harvey Genung)
_Florian Mayr_ (N.Y.: B.W. Huebsch) 14: It was half past nine in the morning
of the eleventh of November, 1879. It was a day like any other. Florian Mayr
had risen as usual at eight, had made coffee, and then as usual had played
scales and finger-exercises for an hour.

By 1975, my office mates and I were using it humorously and frequently.

JL

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