Any NIN fans who have never heard "still," the least-guessed answer here, should definitely check it out. Originally released as a bonus disc for the live album "and all that could have been," even as a standalone album it's one of my personal favorites.
If this one got taken more times I may have made more quizzes on the subject of the greatest band of all time, but apparently there aren't a lot of NIN fans at jetpunk.
Updated for Bad Witch. Just saw them in concert twice at Anthem in Washington DC. Kicking as much ass as ever. Both shows were incredible, and only four songs in common from the set one night to the next!