I don't know if someone posted this but here goes.
I think that LimeWire should be able to search many servers at once. I have many programs that do this, but they are slow and sometimes crash trying to download files. When i don't get a file that i'm looking for in LW i think that another server might have. I know that this is not likely going to happen because LW is controled by Gnutella Network and must only stick to it. It's still a hope.

Your use of the term Server is unfortunate. Since all files shared are shared by people like yourself. That's what it is, peer to peer (p2p.) As far as using other networks, the problem is those programs that are multi-networked, fail miserably because if they're connected to more than one network at a given time, then their bandwidth gets used mostly on one of them. This means they're very difficult & slow to downld from. They will also upload from you slowly. At least one of those networks demands they can only downld as fast as they upload, ... so get my point about the bandwidth being not fairly shared. If they could only be connected to one network at a time, then that would be a different story.