Interacting with living, non-human beings is one.
At least until today. Mindworks Innovation Lab's Aquard.io has come to our attention, and it might be our favourite way to give food to an animal using nothing but our browser. For this is a web app that looks like those 'feed the fish' toys from the early days of the iPad, but actually involves real, living fish.
The system was made as a way both to relax users, and literally to feed the fish on time. You log in to the website and wait in line to press a button and release more feed into the aquarium.
You can also press a 'bubbles' button to shoot a jet into the water and choose from several different views of the various piscines within.
It was made by hooking up an Arduino Uno computer to the feeder. (There are more details about how it was done here.) It's not quite as good as those dogs who Skype with each other, but it's close.