Reducing Arduino Power Consumption
Contributors:
Alex the Giant
Alex the Giant 
Resources and Going Further
More information on low-power modes and options can be found in the datasheet for the 328P.
For more power-related fun, check out the following SparkFun tutorials.
LilyPad Basics: Powering Your Project
Learn the options for powering your LilyPad projects, LiPo battery safety and care, and how to calculate and consider power constraints on your projects.
IoT Power Relay
Using the ESP32 to make a web-configured timed relay.
LuMini 8x8 Matrix Hookup Guide
The LuMini 8x8 Matrix (APA102-2020) are the highest resolution LED matrix available.
Getting Started with the MyoWare® 2.0 Muscle Sensor Ecosystem
The MyoWare® 2.0 Muscle Sensor, an Arduino-compatible, all-in-one electromyography (EMG) sensor from Advancer Technologies. In this tutorial, we will go over the features and related shields to connect the sensor to a muscle group.