Making multiple RSS feeds for the blog website

Hi everyone, We are developing a blog service website. What we need now is the ability to make multiple RSS feeds from several pages (an RSS of each user's blog, a feed from each timeline - timelines are our representation of users' favorites; a feed filled with comments to a separate entry, etc.). What would be great is the following: a user enters, say, in my blog and sees the mark that there are RSS feeds. Then he/she clicks the mark or presses a keystroke (Alt+J in IE8, for instance), finds the feed and double-clicks on it. Then he/she can either read the feed or subscribe to it. The feeds have usually file extensions of .rss or .xml. Question: how do we do that with PHP? Thanks! -- With best regards from Ukraine, Andre Skype: Francophile Twitter: http://twitter.com/m_elensule Facebook: http://facebook.com/menelion