I think it's fairly understandable why - of all of Asimov's shorts - The Last Question tends to have so much gravity with HN readers. For those that haven't read the story before, I can also see why it's worth the up vote. I do find it perplexing, however, to learn how many times it has landed on the front page. This is personally the third time I've found it front page in the last 3-4 years - and I'm not a die-hard HN reader.

At any rate, given how many readers are probably new to the The Last Question, it's probably worth citing another Asimov piece that is oft-mistaken for The Last Question - The Last Answer. It's a more recent work, and a bit more obscure, but worth the read if you're into Asimov.

http://www.thrivenotes.com/the-last-answer/