How to make an inexpensive but VERY bright LED flashlight

We all have seen, and maybe even own at least one, LED flashlight.  The lights can be quite handy and durable, without the fear that you are going to suddenly have a bulb burn out on.  The lights tend to be much more miserly with the power as well, letting the user carry a smaller package for lighting that also has an impressive battery life in the field. As you can see by the list below, LEDs offer many advantages over standard incandescent lighting:

However, one thing that LED lights are not typically known for are their extreme brightness.  Typical LED lights run in the 40 lumen range, enough to be of great help in the dark but maybe not in the "comfort" range. But by combining LEDs you can greatly increase their total output, and options are readily available. For example, you can buy a bright multi-LED light from places such as Amazon (where you will find a very bright 160 LED light (Amazon.com) perfect for those hacking DIY needs).

But Youtube user Jayandersons has his own solution for adding more umph to a LED light.  His interesting project takes a $23 SSC-P7 LED unit and hooks it up to a $10 light, making it 20 times brighter and upping the total output to an impressive 900 lumen.  This is claimed to be enough to shoot a beam of light over 3 miles, not to mention light up a room quite cozily.

CAUTION: Please note that the info presented herein is for educational purposes only.  Improper use can cause injury. 

(Thanks to Bill for the Tip)