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.
LTC4150 Coulomb Counter Hookup Guide
A "Coulomb Counter" is like a gas gauge for your battery. Here's how to use it.
LilyPad Simple Power Hookup Guide
A basic guide for getting started using the LilyPad Simple Power with LiPo batteries.
Mean Well LED Switching Power Supply Hookup Guide
In this tutorial, we will be connecting a Mean Well LED switching power supply to an addressable LED strip controlled by an Arduino.
ATX Power Connector (4-Pin) Breakout Hookup Guide
Do you need to power a project with 12V and 5V from one wall adapter? The ATX power connector breaks out the standard 4-pin computer peripheral port for your 12V and 5V devices!