March 3, 2009 is square root day.
CNET points out:
Tuesday is Square Root Day, a rare holiday that occurs when the day and the month are both the square root of the last two digits of the current year. Numerically, March 3, 2009, can be expressed as 3/3/09, or mathematically as √9 = 3, or 3² = 3 × 3 = 9.
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