Old broken Android phones used as wireless cameras. Broken dvdrom from PC used to rotate camera as needed. Had to build motor controller circuits with brand new parts and ic's that I ordered from China though. And had to install the camera software onto the phones using adb from the PC using USB cables as the screens don't touch, some don't show at all.
Also using an old dell PC to display the various camera feeds with a web server and a web page I programmed myself.
Been running flawlessly for over a year now.
Even sold a setup to my neighbour. He has no complaints

BTW..it's wireless so you can view the feeds with anything that can connect to the internet.
When I had flow internet I could view the feed from anywhere there's an internet connection after setting up port forwarding on my server and setting the server as the DMZ host , but since I switched to digicel play, I could only view from my home network.