Gelatine
Made from bones ( small or big ) or sines and wood on cooker with pot.
From gelatine, sugar and fruit it would be possible to make gelly sweets, jellies (polish 'kiesiel') etc.
Idea has a huge YES on polish forum and also a great number of ideas for using gelatine.
Everybody on our forum agrees that there is a need of making something from useless animal remianings. Thats why gelatine (also because everybody like jellie ;P) should be implented (from my and most of polish players point of view).