In reply to neuromancer:
I've one of the Tikka RXPs and it's been really good for running, esp with my wife as I now inadvertently blind here about 75% less often per run.....
Only circumstances I've found it lacking have been when cycling (anything reflective, or traveling towards you gives it a false high feedback resulting in it dimming), or when doing stuff that involves looking towards people using torches as well (their torches trigger the sensor and make it think it's lighter than it is, again dimming the torch).
My wife has the ReVolt and likes it for running through the winter (forest trails mostly). Definitely bright enough for that.
Both can be charged directly via USB, but the battery supplied with the ReVolt was rubbish, replaced with a different set of rechargeables and works a charm though.
Have a look at fenix torches. I've only used their bigger ones, but they've been good torches (though not the best headbands).
Cheers,
Stuart