One non-free package which can be replaced relatively straightforwardly: mpg123 (non-free) is approximately equal to mpg321 (in main)
Just a datum point - I expect I'll now get lots of people contradicting me but one package would be a start :) To reiterate one of my points in favour of Debian and the Debian Project infrastructure being considered entirely as DFSG-free: if as a project, we were to concentrate henceforward only on DFSG-free software, it might be easier for me to convince my bosses that they could use Debian more freely and not risk paying large licence fees / face copyright infringement [which I can't categorically say for any commercial distribution]. They are worried by FUD. Now that HP have come out in support of Debian, thankfully there's one argument less over "who can we get support from / who can we sue" :) Andy