This is a basic project to display a public Google calendar on a low-power e-ink screen, suitable for doors to show when the room is free or the occupant will be there.
Hardware used: https://www.tindie.com/products/squix78/esp8266-29-espaper-plus-module-e-ink/
It wakes up once a day, connects to the specified wifi network, synchronizes the time through NTP, and retrieves the entries in the specifed Google calendar for the next 5-7 days, depending on what day of the week it runs on (weekends are excluded). It then does some rudimentary parsing of the entries and displays time and title.
There's no checking for overflows of any kind, i.e. event titles too long or too many events for one day. Up to 4 events a day fit on the display, and titles can be a word or two.