RSS was intended to doing that.
Blockquote RSS stands for “Really Simple Syndication” and it’s just a stream of data . If you click this icon, you’ll be subscribing of a specific research using the RSS reader. By email. With email subscription you will receive notifications via email.
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Blockquote Sparkle will produce an RSS feed automatically when you create a blog . The feed will be visible both in the blog and on the home page. If you have multiple blogs the home page will expose all of them. The way these are exposed is machine readable, using a rel=alternate link in the page code.
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Hope that helps.