Of course this whole route is much cheaper if you have a charger like a Maha 777...
As far as camcorder (and phone---mostly phone) batts go, be careful! There are some out there with rediculous mAh ratings. (Reduculously low, that is)
SO with this in mind...I issue a challenge. No I won't buy the final product, I can't afford it! But here's the challenge:
Use a camcorder, cell phone, or other rechargable 3.6 volt battery. Circular, round, it doesn't matter.
Turn the battery into a flashlight. Standard formfactor flashlight. Round body. Smaller is better.
Develop a way of charging the battery without taking it out of the light. The charger doesn't have to be "drop in," you just have to be able to put the flashlight on the charger without dis-assembling it and it should take less than 5 seconds (After practice--10 before) to put it on the charger.
Who'll step up to the plate? Comeon! (I can't believe I am goning to say this) put the Arc LS to shame!