Getting more from a single battery charge

There are very few tech-related things that are more annoying than having your portable device "die" on you when you need to use it simply because you had forgotten to charge it up before you left home, but what if you did forget to charge it up?  How can you get the most out of the remaining "juice" in your battery?

Here goes:

1. Keep the device's (laptop, smartphone, tablet etc.) screen/display at the lowest usable brightness level possible.  
2. Turn off wireless features such as WiFi and Bluetooth if you're not using them
3. On your smartphone you can also turn off the GPS receiver (if it has one)
4. If your battery is running low you may also want to avoid processor-intensive activities such as the playing of games, copying of discs and viewing of videos
5. On laptops you can also unplug any USB peripheral device that draws power from the USB port if that device is not being used
6. You should also consider putting your laptop in hibernate mode instead of sleep mode if the battery is low and you'll be needing to use the device intermittently.

SEE: http://www.jadabreo.blogspot.com/2012/08/best-battery-care-practices-for-laptop.html