This was the original project on Hackaday:http://hackaday.com/2010/03/26/thats-a-big-flashlight/
This is the datasheet for the CBT-90 module:http://www.luminus.com/products/CBT-90_6_1830406983.pdfhttp://www.luminus.com/products/CBT-90_6_767904390.pdf
You can buy the CBT-90 module from Mouser:http://www.mouser.com/Search/ProductDet ... YnoQ%3D%3D
The module might be less time consuming and possibly less complicated than soldering 500 Leds.
This page shows their module that will deliver 6,000 Lumens. It is their highest output general lighting led:http://www.luminus.com/products/CSM-360.html