I have the computer box, a dish/plate, one of the speakers and a glass window. if they are slow zombies, I'll smash them with the comp. box, if they are easy to kill, I'll use the speaker as a sort of flail or other melee weapon, and if they bleed I'll smash the window and try to find a pipe or something, make a spear out of the glass shards. Or use them as knives.