You ban them ..... but don't go yet! It is rarely that simple .
Today I banned a host, I think with justification. He queued up a large list of my tunes and I browsed his share. He was sharing 16 songs. He said he was connected by modem, and yet he was uploading from me at a very good cable speed. I tried to download one of his songs and got the permanently busy message. I believe he was deliberately stopping uploads, thinking possibly that this would speed up his downloads Didn't work he he.
The fact is that for a number of reasons a host may appear to be not sharing, but because of firewalls, strange ip nos like 192.168.xxx, which are in fact not the hosts real numbers ...(not quite sure how that one works but DON'T block hosts using this ip no as suggested in a thread which was posted a year or more ago, as some hosts using that ip no are totally excellent) and simply hosts who download perhaps on their wireless lap top and share from their other computer etc. etc...
I recomend you read this thread, and then decide what you want to do
http://www.gnutellaforums.com/showth...ght=freeloader