Take out the Great Fairy's Sword and walk up to a postbox. Try to insert the Fairy's Sword. The postbox will reject it, but Link will have his arms outstretched, like he's holding the sword, but you'll be holding onto nothing. Press the Fairy's sword C-Button, and Link will swing the invisible sword. It still slashes at stuff. It'll be fixed if you use another item. You can do this with other items, like the hookshot (but not the bottle for some reason).
Submitted by: Michael