[PodeCoet] sent in this mod he did to a Spider Fire flashlight. These things are unbelievably bright, they use Cree LEDs that are so intense, they can ignite paper. [PodeCoet] notes that they run on fairly expensive batteries. Instead of buying some rechargeable ones, he decided to customize and hack his torch. He added a custom charging circuit and a Lilon battery as well as a boost-converter circuit and a status LED. We like the idea of having a rechargeable lamp, but he has lost his water proofing. If anything, you should go there to see his nicely done smd charger pcb as well as the pictures of his test run, burning some paper.
As some people have pointed out in the comments, this flashlight could not have started that fire. This one could though.