For drag and drop, you have some choices... You could make your own implemetation of cellRenderer that includes that functionality... that might be doable. Or you might find some third party solution that does that or makes it easier to do it. If you go that route, I have a List Box alternative here ...
http://www.layer51.com/proto/d.aspx?f=1396. It might be a little easier using it as a starting point than the MM list box... hard to say. If you do, let me know... I'll try to help and it would be cool to add that functionality to the prototype site.