Does it look like this?:
That's an indication that this site publishes an RSS webfeed. There's a pretty decent explanation of what RSS is (it's nothing scary!) on the Beeb:
http://news.bbc.co.uk/1/hi/help/3223484.stmBasically, it's an indication that this site is published in a parallel format that feed reader software can understand, so you can keep a continually updated eye on the site without actually having to be here. Most newspapers, blogs, forums, and other 'live' webpages like this use RSS, so you'll probably see the logo elsewhere too.