Morpheus said:400+ minis = plastic baggies (sorted by type) and in plastic storage boxes you can buy at Wal-Mart.
Me too. Sorted by "winged monsters" "demons" "elementals" "miscellaneous monsters" "orcs" "goblins" "evil humans". I think that's it.
I use a Wal mart compartmentalized organizer for the lead ones. That's not a great system, but I haven't run across anything better than the tackle box for metal minis.