Well, it's time to begin fill up this section with some tips
A lot of people must have encountered the situation that you are collecting a series (TV, pics, comics, anime, whatever) and you only need one or a few files from a multi-file torrent to complete it.
Normally you would need to download the whole torrent or substitute the files from the torrent with your own (with obvious problems of the files having to be exactly the same).
However you can use the BT client Azureus to select files from a torrent you want to download.
When you start a torrent with Azureus you can select the 'Files' tab in the download window:
Now select the files you DO NOT want, right-click, go to 'Set Priority' and choose 'do not download'.
Warning: The client doesn't remember the priority settings after a restart, so you need to re-prioritize when Azureus restarts.
Warning2: It seems that there is some incompatibility between the file-checking of Azureus and other clients. Consequently Azureus may not resume torrents at the percentage you reached with another client