RSS feeds are great. Feedburner really does all the work for you, if you have blog or a site that generates RSS. Most blogs do. Usually the only thing you need to do is find the url of your RSS. You to to feedburner and paste that url into the field they give you. It will generate a code, and you put that code into your blog. There are many other services too, but feedburner, I think, gives you the most options.