Just a quick idea i did a search and it didn't turn up much.
I was just thinking it would be a neat to be able to put poison in food and it cause sickness to whom ever eats it.
Sickness could be a small temp loss of stats and random -hp tics chance to throw up food eaten while sick and maybe black fep's as a result different foods have lower chances to cause vomiting ie creamy cock soup 1% of vomiting and 20% at removing the sickness debuff.
Or a hunk of meat a bit of string and a live rabbit to catch foxes (drop the rabbit after crafting the poisoned live bait and hope the fox chases it). Or you could use poison on our blades for a chance of poisoning those you attack only a temp weapon buff though.
How about a spy poisoning the village well.