DIY project: Build a Long Lasting Battery Pack for Your Compact Camera to Make Time-lapse Videos
Compact point-and-shoot cameras are wonderful for time lapse photography. You can leave them out for hours or even days without tying up your main camera, even the lowest resolution point-and-shoot creates images big enough for high definition video, and if they get stolen or destroyed you haven't lost thousands of dollars.
Their one flaw in this application is battery life. Luckily with this DIY project, you can build a battery pack that will allow for your camera to stay on far longer than with the normal batteries.