I'm a big fan of using feed aggregators, more specifically Google Reader. If you've never tried it, you really should. Instead of keeping a list of bookmarks to favourite sites and checking them regularly for new content, I add them to the reader. It also allows me to manage what I've read, what I want to tag for later, what I want to share... I hardly browse the web anymore. When I visit a site I find interesting, or a product I want to be informed about, I just use the feed. When it doesn't have one, or it's not working, I don't bother. So before reading on, check if you're site has proper feeds -- you could be losing part of your audience!
Easy feeds in Joomla!
It's even more frustrating when I see a Joomla! 1.5 site that doesn't have proper feeds. J!1.5 makes it so easy, and still some people manage to mess it up. By default, when you make a new menu item to a category, a section or a frontpage, the 'Show a feed link' option in the Advanced parameters box is turned on. The new page you created will have a feed icon in the address bar in most modern browsers. By clicking that, you get a choice of RSS and Atom feeds to subscribe to.
It gets better: When you turn on 'Search Engine Friendly URLs' in the global configuration, as well as 'Add Suffix to URLs', a URL to a section or category view will look something like this: http://example.com/my_alias.html (or http://example.com/index.php/my_alias.html if you're not using mod_rewrite). Now change the .html suffix to .feed, as in http://example.com/my_alias.feed.
Instant gratification! (The same principle applies to articles, try changing the .html suffix of an article view URL to .pdf).
Doing more with feeds
The next step is to use some of the web services out there to add some extra power to your feeds. RSS and Atom, the most popular feed file formats, allow for great flexibility. One cool service is Feedburner. It allows you to optimize your feed, publish it to other services, track the usage, ... Another one I can definitely recommend is Yahoo Pipes. It has a graphical interface that lets you mash up, sort, filter, and even translate your feeds.
What these and other services have in common, is that they generate a new url for the resulting feed. Your users will need to use that feed, else they're bypassing all the cool features you added. A simple solution (though arguably not very flexible) is to insert the new feed link in the <head> tag of your Joomla! template. This will make the same link appear on every page. Of course you also need to turn of the 'Show Feed Links' option I mentioned earlier.
Nooku.org: a case study
All of this might sound a little abstract, so I drew up a little schema of how we do it on nooku.org. Hopefully this gives you some ideas to start exploring.
