When downloading some torrents the last few percent are sometimes really hard to obtain for whatever natural reason. I would like to help these torrents survive, but I don't want to participate in uploading the bulk 98% that is easily available already. I make it a rule of mine to seed a torrent for at least twice the weight, especially for public torrents, but with these hard-to-get torrents, I would like to seed only those hard-to-come-by parts afterwards.
Maybe it would not be too difficult to create an option to seed only those parts that are low in availability? I sort of see this kind of information in the Details tab on the third bar, that some parts are rarer than others.

Thank you for considering.

Each Bittorrent client should prioritize the rarest pieces first by default, however these days there are a lot of clients downloading sequentially. The option you want is basically Super Seeding which is already available in Tixati. According to Help & Support
I don't know exactly how it behaves after initial seeding of a torrent, but at worst it offers random pieces instead of all pieces to peers. It would be great if the Super Seeding feature would offer rarest pieces first, so that it would be useful after an initial seeding. Maybe it does already, I'm not sure.

If I may, I would request to add a separate status for Super Seeding torrents. Right now Tixati displays them as usual seeds with Seeding status. It's hard to find which transfers are at Super Seeding mode.

only problem with super seeding is, after rework in version (dunno 2.15?) its broken and will only communicate with few selected clients with proper SS implementation?, others get disconnected, one of them being utorrent, you see problem here, since utorrent is like biggest out there and you cant connect to these peers with SS activated, making whole feature really bad for seading, more compatible approach would be better

I missed the obvious, at transfer's Options > Seeding tab is a Super Seeding description: "Force rarest-first distribution of pieces". I tested Super Seeding on a torrent full of sequentially downloading clients for a night. From observation it seems Tixati offers mostly rare pieces close to the end.

http://s7.postimg.org/6qw1xdikb/tix01.png
http://s12.postimg.org/ulx6hdrzx/tix02.png
http://s22.postimg.org/cg9ira59t/tix03.png

For me the ideal number is upload in sequecial way, because whenever new part were sent this new part would always be the rarest, and then help a lot to those who want to kind of stremming to see just the movies do not have the work force download in sequential mode!
Upload sequentially for me would be the best thinking think Tixati of User would give great lesson for all the torrent community

consider:


wiki.vuze.com/w/Sequential_downloading_is_bad

Sequential down or uploading is not the best (to say the least), the BitTorrent protocol is NOT meant as a video streaming service, the clients are meant to share files as a whole and as fast and as efficient as possible. Sequential seeding is not efficient because leechers will have the same pieces and nothing to share between each other and absolutely rely on the seededers. If there are no seeders but the availability of the torrent between the leechers is greater or equal than 1.0 than they are still able to finish the download. With sequential seeding the leechers cannot do that and will not finish the download when the last seeder goes off the torrent. Sequential seeding is a horrible idea.