April 4th (4/4) is International Rock Beat Day. A "rock beat" or "common time" is four beats per measure of music, the standard rhythm of most popular western music.
"We've got to play some Beatles records on April 4th... it's International Rock Beat Day!"
international beat-off day is an offensive term because on these days otherwise productive male members of the North American workforce simply sit at home doing diddly-squat and beat off to porn. Too bad Thanksgiving is not celebrated in Canada during the month of Brovember.