We’ve just launched a new Rails-based chat/microblogging site at
http://rejaw.com. I mention it here because we are using ferret/aaf to
index all our content, as we did on Lingr.
Our index isn’t as big as Lingr’s yet (that’s over 21M entries), but you
could help us out with that by participating 
Check it out and let us know what you think!
Best Regards,
Danny B.
http://rejaw.com/help/about#danny