One sits in my bathroom so I can browse random Wikipedia articles while I'm, uh, busy. The other one sits on my nightstand and plays audiobooks/podcasts when I'm going to sleep.
So nothing critical. But something they are still good at, and being very small makes them a natural fit for these use cases.
I can't speak for the other poster, but I like the idea a lot. Having tools with specific purposes means I can avoid using my phone for everything. No matter what games I play to remove notifications/interruptions/etc. it's always a distraction and easy to be distracted from whatever I originally intended to use the phone for.
I do use the phone for audible, but I started both uses before I had a smart phone (I was very late to the game), and I am a creature of habit. Plus the netbook has a bigger display, more storage, and a real keyboard (again, creature of habit).