uBoost Single AA to 3.3v 100mA Power Supply
https://www.electronics-lab.com/uboost-single-aa-3-3v-100ma-power-supply/
µBoost is a Single AA powered, 3.3v 100mA power source and flashlight and it can run low power devices. µBoost is small, portable, 3.3v 100mA power source for low power devices like Arduino Mini. It has white power LED and can usable as flashlight. Also it has “Battery OK” indicator that asserts when the battery […]
Smart LED Flashlight
https://www.electronics-lab.com/smart-led-flashlight/
Vitaliy_M @ instructables.com has build a nice little LED flashlight. The flashlight turns on automatic for 60 seconds when it senses that the room is dark enough. To turn on manual light for additional 60 seconds you need to push the RST button. Smart LED Flashlight – [Link]