I saw this and bloom filter was my very first thought, so I'm glad you had it. We used it to check if you had voted on a discussion on reddit. It almost all c

I saw this and bloom filter was my very first thought, so I'm glad you had it. We used it to check if you had voted on a discussion on reddit. It almost all cases the user had not voted, so it was a lot quicker to check if you hadn't voted than if you had.