Yesterday was D-day, a significant day for USAns. It was also 6/6 (June 6), a Tuesday. The days 4/4, 8/8, 10/10 and 12/12 are also on Tuesday, as are 7/11, 11/7, 9/5 and 5/9, and the last day of February. The phrases even-even, seven-eleven, and nine-to-five are useful mnemonics.
You can use this pattern to figure out the day of the week for a given day. For intance, 12/25/00 is one day shy of two weeks after 12/12 (d-day), so Xmas is a Monday this year.
In non-leap years, the last day of January is a d-day, but in leap years, the first day of February is a d-day instead. Xmas is always the day before d-day.
I almost forgot my general question: is this MPS?