I use Home Assistant to set my smart light brightness and colour temperature to different values based on the time of day and position of the sun. This (apparently) helps keep your lights in line with your circadian rhythms for better sleep and mental alertness. I use a combination of template sensors, automations and the circadian lighting HACS plugin to achieve this.

Links:
My Smart Light settings (Blog post): https://www.homeautomationguy.io/home...
Making your smart home guest friendly:    • Making your smart home visitor friendly  
Home Assistant Community Store: https://hacs.xyz/
Circadian Lighting plugin: https://github.com/claytonjn/hass-cir...