Someone made a desktop application much like that, it was wonderful, truly wonderful... until I started chatting with the developer about not keeping semi-permanent logs of who [previously] hosted what. I had hoped to solve the puzzle but he started unpublishing his application immediately.
I think simpler things could help more. I would like to see 1) a client that (in stead of just seeding) periodically checks how rare the rare blocks are on a torrent then seed just those blocks. 2) attempt to extend the tit for tad by looking for similar titles and file names (or some other formula) if insufficient seeds are available. So you might have [parts of] foo1 and foo3 and are looking for [parts of] foo2. foo2 is served by someone looking for [parts of] foo3. One could even ask to help seed something they are uninterested in and/or unfamiliar with. It does seem less of a "crime" than getting involved in permanently seeding the motherload.
I think simpler things could help more. I would like to see 1) a client that (in stead of just seeding) periodically checks how rare the rare blocks are on a torrent then seed just those blocks. 2) attempt to extend the tit for tad by looking for similar titles and file names (or some other formula) if insufficient seeds are available. So you might have [parts of] foo1 and foo3 and are looking for [parts of] foo2. foo2 is served by someone looking for [parts of] foo3. One could even ask to help seed something they are uninterested in and/or unfamiliar with. It does seem less of a "crime" than getting involved in permanently seeding the motherload.