Some of the best things I have seen NWN characters get attacked (and/or killed) with:
Umbrellas (evil rogue character dresses up as a lady, defends her honor with her umbrella, getting sneak attack damage)
Dead Babies (used effectively as a club... again, sneak attack damage was applied, making it the most dangerous dead baby ever)
A book (my wizard on another server got caught during his studies and promptly died after managing to do about 5 points of damage with his spellbook)
A violin bow (bard/rogue would be deadly with this item)
Wishlist:
A ladies' fan (think Japanese war fan with razors in the end)
A ladies' handbag (throw some ball bearings in the bottom, you got a sap.. haven't seen one in the toolset yet, but i just know someone will make one that is equippable in the weapon hand)