I would definitely go with Direct Connect (www.neomodus.com). It has large amounts of people sharing GB's of files. I have seen up to 30 TB's of info on a single hub there. It supplies you with a list of all the network hubs so you don't have to search or download a list like you may have to do with WinMX (www.winmx.com) and some others. It is also very high speed friendly due to the fact that it is a peer to peer with over 75% high speed internet users.