Bees. They're just like us. (It's not clear to me that this research will actually lead to practical applications, but it's a cool experiment even if "caffeinated bees" sounds somewhat nightmarish.)
Caffeine Boosts Bees’ Focus and Helps Them Learn
By associating caffeinated sugar-water and a target scent, researchers teach bumblebees to stay on task
scientificamerican.com