If you are going to try all the instances of a file with 'download all' then why not let them download pieces of the file from different hosts simultaneously. Since most hosts are throttled down to limit bandwidth use, it would be possible to get a download at your own full port speed if you could get a few of them transmitting to you at the same time. LW would have to keep track of the pieces and assemble them. The user should be able to say which files are the same, regardless of the file name. LW could use a checksum to validate that the file is the same.