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.
Battery Technologies
The basics behind the batteries used in portable electronic devices: LiPo, NiMH, coin cells, and alkaline.
LilyPad Simple Power Hookup Guide
A basic guide for getting started using the LilyPad Simple Power with LiPo batteries.
Blynk Board Project Guide
A series of Blynk projects you can set up on the Blynk Board without ever re-programming it.
Current Sensor Breakout (ACS723) Hookup Guide
Learn how to measure the current consumption of your project using the ACS723 Current Sensor.