This is extremely simple so dont expect too much and its just a minor twist on content networks that pull in your RSS feeds.
I was thinking about all the unique content that is generated on twitter every minute of everyday, and it struck me that its only a hour or so's work to actually use this for alternate purposes.

I am not suggesting that you do this however you need to be aware of just how easy it would be for someone else to do it against your sites

Step 1: Pick your topic lets say pubcon
Step 2: check for hashtags related to e.g. #pubcon
Step 3: Go to yahoo pipes
Step 4: Clone http://search.twitter.com/search.atom?q=%23localgovweb&show_user=true and edit to use #pubcon
Change http://search.twitter.com/search.atom?q=%23&show_user=true to be http://search.twitter.com/search.atom?q=%23pubcon&show_user=true
Step 5: Clone http://pipes.yahoo.com/pipes/pipe.info?_id=ac45e9eb9b0174a4e53f23c4c9903... and change it to clean up the first feed with the frist pipe you created
Step 6: Grab the RSS feed url
Step 7: Do a bog standard install of Drupal and enable the aggregator
Setp 8: Add the url to aggregator and add some tags
Step 9: Launch you new pubcon focused site with loads of constantly updated fresh topical content that has been stripped of all the stuff that would identify it to google as being rehashed (pun intended) twitter posts.

Ok I know this is noddy stuff and nothing very exciting however if you take this a step further and install the Feedapi/CCK/Views/Feedapi mapper modules for drupal and expand it to do something simple like have yahoo pipes pull in most active pipes on specific topics this could actually be quite a formidable content generation tool.

And before anyone beats me up yes I can see the flaws I am just trying to highlight how things can be looked at from different viewpoints.