one of those box things people that sew use to hold their threads and stuff, with slide out draws and all. Dunno what they're called. A tackle box could be used, with the compartments up top for minis you will need for this game (NPCs and PCs, monster encounters, etc), and the bottom can be a dumping ground for all your other minis. I don't know how many you have, so that might not work...
Personally, I have them all in one of the boxes from the entry packs..
Good luck!