It's bad enough to get hit on the head with a MagLite, but here's one that'll burn your house down too.
All right, so it's been slightly modified. How'd they do it? Twelve 1.2V NiMH (rechargable) batteries capable of a sustained 10 amp draw--encased in that sturdy skull-cracking MagLite body--and an Osram HLX 64623,12V bulb "which is being overdriven to 14+V, to about 140 watts, with an estimated light output of about 4000 lumens." A regular 2D MagLite puts out less than 50 lumens, according to Mr. McCracken at extreme-geek.
The reflector is made of metal, as a stock one "would melt almost instantly from the heat of the Osram." The original switch has also been replaced with something meltproof.