Hi there,
   did anyone come across yacy[0]?
   It's a crawling software, that creates an shared index within a defined
   realm.
   I can say that it's OSS (GPL), but I had no time to inspect the code.
   I'm wondering, what's this list's opinion on it.
   Cheers,
   frk
   [0] [1]http://yacy.net

References

   1. http://yacy.net/