MacRumors had a PHP page that gave up to the minute details on Steve
Job’s keynote at MacWorld by using AJAX to refresh the page at
regular intervals (thus keeping users from constantly reloading the
page). They have posted details about their system as well as some
To summarize, they served 32GB of data in a three hour period. They
estimate that they would have served 196GB of data if they hadn’t
used AJAX. That’s a reduction of 84%.
Even though it’s PHP and not Rails, I thought the list might find it
interesting. It might also help someone sell a client on the
benefits of adding in certain features to a project.