Quad-Magnet Childsafe Cabinet Key
This is a holder for a stack of magnets. Once sealed it becomes a (relatively) child-safe object that will open these magnetic child-safe cabinet locks:
This solves the problem of losing the key that comes with the locks, having a key that is a color that displeases you, or of paying too much for the replacement/extra key:
http://www.amazon.com/Safety-1st-Magnetic-Locking-System/dp/B004FI7USI/ref=pd_bxgy_ba_text_y
Note that you may be able to use one large magnet rather than a stack of four. I just had a ton of that kind of magnet on hand.