I personally enjoyed the variant based on a 2E spell from one of the Wizards Three articles called Boneblast (I think). You could cast it on any unanimated bone as a trap. You could also cast it on an unanimated skeleton, then animate the skeleton (or zombie if there was enough skin still on the bones in question) - when it was dropped below 1/2 hp, it would explode in a storm of bone shards.
I had some evil priests do this with zombies...
Take cadaver, open abdomen, clean like thanksgiving turkey, cast spell on revealed skeleton, get small beer handcask, drink beer, fill cask with contact poison and penny nails, seal cask, put cask in cadaver hollow abdomen, sew cadaver shut, animate zombie, post walking bomb as guard.
My players NEVER treated low level undead the same again.