Tiny NFC-Powered Keychain Thermometer
![ATTiny NFC Thermometer keychain with keys](https://hackaday.com/wp-content/uploads/2024/12/thermal-keychain-1200.jpg?w=800)
What if your keychain could tell you the temperature, all while staying battery-free? That’s the essence of this innovative keychain ‘NFC_temp’ by [bjorn]. This nifty gadget harnesses energy from an …read more Continue reading Tiny NFC-Powered Keychain Thermometer