A DIY MP3 box with NFC ! In order to choose your your songs, you have to pass a NFC tag. 5 buttons in to pause, prev, next, lower/upper.
A digital thermometer built from scratch using Attiny85 and ds18b20 temperature sensor, which can run on a CR2032 over 130 days!
Use to record somebody's blow strength. Since without calibration it is relative value.
A thermostat with an OLED capable of plugging into a USB port.
This is the 2nd tutorial on my ESP32 learning journey. Here, an OLED shows time and captured data by DHT sensor (temperature & humidity).