Mine aren't original but I have a classic game emulator using Retropie and SNES style bluetooth controllers. I also recently set up another Pi using the Pi-Hole software for a network wide ad/tracker/crap blocker on a network level. Its a DNS filter for your whole network including anything on WiFi. Was real interesting to see how my much my 3 Roku's were connecting to logging servers (they no longer can thanks to this).
I'd also like to set up a surveilance camera system.......just not sure its really economically worth it when the Pi can cost 35 bucks, the camera 25 bucks (official camera) and thats not including power supply, case, etc. Its something I want to look into more.