I agree with this comment. There some web apps with no backend, like the games providing a hashbang url like "#!/game/1" for each session, storing the data on t

I agree with this comment. There some web apps with no backend, like the games providing a hashbang url like "#!/game/1" for each session, storing the data on the browser. No backend means, we need to pick index.html as 404 page (I never prefer this way), to implement same thing without hashbangs. And there is no explonation for these kind of apps, in this blog entry.