If you search for "ESP8266" (especially on a website like hackaday.com) you will see a lot of projects using these boards or very similar ones. You can also look up the ESP32, which is the big brother of the ESP-8266 with Bluetooth LE, more CPUs, and some other cool features.
https://steve.fi/Hardware/helsinki-tram-times/
But you also find out about constraints too. Driving an epaper display without running out of RAM was a fun challenge:
https://steve.fi/Hardware/d1-epaper/