We've got things like the Stick for Farfetched', the Lucky Punch for Chansey, Ditto Powders, etc. What are some species exclusive items you'd think would be fun. They don't have to make it good in competitive (though they can)

Hard Mode: Avoid stuff for for your OU and Ubers teams that make them even more broken.

Shedinja: Basically Boots and Goggles at the same time.

Wishiwashi: Boosts it's HP the more Wishiwahis are in you're party.

Eevee: Gives STAB to any move of an Eeveelutions type.

Dusknoir: Boosts his defenses above the level Eviolite gives Dusclops.

Vespiquen: Boost the effectiveness of -order moves when Vespiquen only knows =order moves.