Comment by pirates
I use it as a store for all the amiibo data I might want, as well as a universal remote for my TVs and fan/light in the house. I also use it on the TVs and receivers at work when someone misplaces or loses the remotes, and keep a separate one in the car with a few garage codes for my parents and siblings houses.
The wifi board is fun to play with to learn about how some of the more common/basic SSID spoofing and broadcast spam attacks and similar things work. There are some fun HID device attacks you can check out too that are pretty cool. I also used it as a jumping off point to dabble with programming in C and using gdb and stuff like that.
I've just got the wifi board. My initial use case is to see if I can send de-auth attacks to the Ring doorbells overlooking the road/sidewalk in the two new houses just up the street...