November almost rhymes with "remember and 20 (twenny) almost rhymes with money. So? November 20 = "remember money". Before dedollarization wipes it out entirely, money is still what this site runs on, money and Johnny's blood, sweat, and tears. I have a hunch it would always be welcome, but 11/20 is a good day to send some if you have some to spare because it is a handy memnonic. If you ain't got the dough to spare, that's cool, just something to keep in mind for when you do.