DID IT HAPPEN OR WAS IT HEADY FANTASY??
The article also specifically mentioned Amazon.com and another site as doing this sort of thing wrong, and showed examples from their sites. The trick was the way you'd expect to do it (the naive way) has some hidden flaws. The article then gave a better way of doing it involving some complicated math and some simple code. It was in a trendy language. Ruby? Python?
Anyway I'm pretty sure I skimmed the article, but I can't find it. And I had a dream where my friend Pat and I were looking for the article, but all we found was a hand-written version of it (?) and it was missing some pages. When I woke up I wasn't sure if the article had ever existed in the first place, or if I had dreamed it! I'm pretty sure I skimmed it and THEN dreamed about it, but any memory I have of skimming a random website is so flimsy that it may have been part of the dream too.
So if you came across this article please let me know! I have not been confused as to whether something happened or I dreamed it in at least a decade, and I wish it was over something way cooler than a website showing you a better way to generate a list on a computer.
UPDATE: Here it is! gregstoll shares my dreams.