Lighting is just getting more and more... well, more. Exhibit A is the Olympia EX550 headlamp, which cranks out 550 lumens at its highest setting, a ridiculous amount of light that covers pretty much everything in your path.
The EX550 is built around a single Cree XM-L LED bulb, housed in a sturdy impact-resistant pivoting aluminum body that is IPX7 waterproof to one meter for 30 minutes. It weighs 5.2 ounces with two included CR123A batteries installed, and although it feels a touch heavier on the head - probably due to the fact the lens housing extends out a couple inches - the three-band strap and rubber base pad keep it in place well enough for non-jarring applications like hiking, climbing and hunting. People who run - and really, what's wrong with you? - should look elsewhere.
The EX550 has four brightness modes and a strobe mode that you cycle through by repeatedly pressing the single button on top of the lens housing. Waiting three seconds between presses will make the next press turn it off. The button itself is glove friendly, and the problem of accidental discharge (a.k.a. premature illumination) is solved by a lock-out function, activated by holding the button for three seconds while the light is off; just don't look at it while holding it, because it will then blink twice at the high setting.
Battery life ranges from 3.5 hours at the highest 550 lumens setting to 60 hours at the lowest 25 lumens setting. The four settings are all useful for different circumstances, but really you're buying this for the big gun, and what a gun it is. Did we mention the ridiculous amount of light? You'll see well over 100 meters down-trail, and the huge halo gives you a serious amount of area lighting as well. For applications like mountain biking, skiing, or anything motorized - e.g. fast - the EX550 will ensure you know what's ahead before it goes bump in the night.
The only downside is the use of the more expensive CR123A batteries, but do yourself a solid and get them for just a buck and a half each on Amazon. Also, it would be nice to reverse the lighting modes so you could start out in low, but you can cup the light if you're in a tent while you cycle through. Overall it's kudos to Olympia, for producing in the EX550 a high-performance light that is reasonably - even inexpensively, given the power - priced and includes two batteries to boot. Did we mention the ridiculous amount of light?