Making RSS Scale   I've been meaning to write about this since I saw a one-page article on  the subject of RSS clogging websites' bandwidth in NewScientist  back in June. But it wasn't until I saw  this  Slashdot story on the same subject that I knew I had to get my  thoughts down. A lot of sites are suffering from a big problem  mdash;  they are being systematically hammered by RSS newsreaders for new material  at regular intervals.        When I first came across RSS around two years ago and did some reading  up on it, it sounded like another interesting protocol for a nonproblem.  I wondered what was wrong with just refreshing a "What's new?" page.  (I have a natural scepticism towards new and exotic protocols.) Nonetheless,  after RSS established a niche in the realm of informing us,  rolling news style, of new network content, I recognised its usefulness  in this situation. I did still feel that its design was suboptimal, no  matter how many thousands of bloggers now relied on it.  