Short snippet summarizing a webpage?
<p>Is there a clean way of grabbing the first few lines of a given link that summarizes that link? I have seen this being done in some online bookmarking applications but have no clue on how they were implemented. For instance, if I give <a href="http://petewarden.typepad.com/searchbrowser/2010/01/mapreduce-for-idiots.html" rel="nofollow">this</a> link, I should be able to get a summary which is roughly like:</p>

<blockquote>
  <p>I'll admit it, I was intimidated by
  MapReduce. I'd tried to read
  explanations of it, but even the
  wonderful Joel Spolsky left me
  scratching my head. So I plowed ahead
  trying to build decent pipelines to
  process massive amounts of data</p>
</blockquote>

<p>Nothing complex at first sight but grabbing these is the challenging part. Just the first few lines of the actual post should be fine. Should I just use a raw approach of grabbing the entire html and parsing the meta tags or something fancy like that (which obviously and unfortunately is not generalizable to every link out there) or is there a smarter way to achieve this? Any suggestions?</p>

<p><strong>Update:</strong></p>

<p>I just found <a href="http://www.instapaper.com/browse" rel="nofollow">InstaPaper</a> do this but am not sure if it is getting the information from RSS feeds or some other way.</p>
