Now that swarm downloading is a reality (and usually works nicely), I have a suggestion. If you're downloading something, and do a search and another instance of that same file is returned (but from a different host), instead of disallowing the download, could that host not be added to the "swarm"? So if early in a search the file I want comes up so I begin downloading, but that host turns out to be slow, I can "add" one or more faster hosts to the download task? Also, the previsouly suggested feature that automatically searches for additional download hosts on a timed basis would be GREAT. Canceling and then resuming downloads from different hosts always causes problems. Between something like this and the rollback feature already suggested (redownload the last 100k or so and check it with the data already downloaded), many of these problems could be rosolved, and downloads completed faster as more download hosts become available. Or pehaps some sort of checksum could be added into the Gnutealla protocol?

Just my small 2 cents.

-James