From Anu Garg’s daily A Word a Day newsletter (though it’s not on his web site:
I’ve been alerted to an event that will take place later this week [today], something that happens once and only once over the course of history. Shortly after noon on July 8, comes the moment that can be called 12:34:56 7/8/9…
It’s not exactly true that this sequence of time/date happens only once. If you follow the day/month/year convention, you can observe the same sequence next month, on August 7.
cleve callison’s blog 
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