Sometimes, due to circumstance, we live in rooms without windows.
This can be a BlessingInDisguise: in warm places, it's easier to keep windowless rooms cool; in cold places, it's easier to keep windowless rooms warm.
For ~$100-200 you can simulate windows with a TV, two RaspberryPis, and a WebCam.
Or you can skip the webcam and use photos or videos that suit your tastes.
If you find yourself living in a room without windows, it's recommended to partake in regular NightWalks to stay fresh.