More ESP8266 Fun!
The Esp8266 can be a very functional web server, hosting pages that let you read from and write to the i/o pins. It also can be a client, posting data to a web / database server (a Raspberry Pi is useful here). With a little more work, it can do both. http://arduinotronics.blogspot.com/2017/11/more-esp8266-fun.html
