the difference between unfixed vs suggested is a bit unclear; As I understand the unfixed does not give any suggestion towards what would be a "good" amount to donate so I chose voluntary suggested donation ("if this was in Ovi store it would be 7EUR, but donate whatever you feel like").

And as mentioned there is some thought/work going towards adding donation buttons to the maemo.org downloads pages (if the packager supplies the information needed).

Edit: and since there is Ovi store (yeah the procedures may suck, you want everyone to pay you fixed amount of money; jump through the hoops) and anyone with the skills can setup a separate repo (which is kinda bad due to fragmentation etc) for their paid SW anyway I suppose the discussion is for software that is not completely closed (though one can upload closed-source packages to extras too).