Toaster. seriously put it at a high enough setting and u will be able to pop flaming burnt toast at people every 2 minutes or so. I also heard that a tooth decays in a day when left in coke, so you could simply get your attacker, skin him to the bone and then put him into a bath of coke, then he will die after about a day
A third one would be windows. Seriously go smash a window in your house and pick up one of the shards. Go on, now, i give you permission.