How can I gently fuck with my housemate?

He's the typical 'never learned housework' type. Never refills the ice tray, cleans the bathroom 2 days after someone else does and tries to take the credit. If you ever bring something up he'll proclaim we all need to do more as if we were just waiting for him to say it. And that's only if he doesn't dismissively roll his eyes and walk away.The friendship is long over, too many 'I misunderstood that letting my cat through the whole house was going to make you sick'. Or he forgot that he agreed to feed the cat somewhere else. Or that his cat ruins houseplants because he doesn't clean the litter tray. And the brilliant reminders he'll choose the cat over me while I'm literally in an ambulance. (Not that I asked him to)The lease is up in August. We're in Australia. I am fucking over it. I don't want to injure or permanently damage anything, but I am done trying to be nice. What's an infuriating habit to start?Freezing vinegar so he starts to refill the ice tray? We already refuse to wash his dishes, and he does them so badly we never tell him to do any 'group' dishes anymore. via /r/TrollRelationships http://bit.ly/2G2iyNu