You can also try KaiDomain which offers free S/H as well. The brightest LED right now is the Cree Q5 at DealExtreme but it's $10/ea and from my understanding from checking message sites it gets 273lm at 1A.

While the Seoul SSC P4 is older it's only a few months old. I mean LED's are advancing at a rapid rate right now. I would not be surprised if in 3-6 months time another company will come out with another LED htat's a few lm's more then the previous ones. HIDs days are very numbered right now with the rapid advancements of LEd's in the past few years. You can already see HID's dropping in price to try to keep people buying them. Right now HID's still are king from all I've read and from those that have both HID's and highpower LED systems. You get the most light with HID's right now but the bulbs are very flakey from all accounts I've heard and there is no guarntee that you won't fall while riding. If the HID takes a hit you have a very high chance the bulb is going be dead where as LED's can take the hit and keep going. Also HID's do not like being turned on/off often where as LED's don't mind being turned on/off and can also be dimmed. Both have thier advantages pending your use. I'm leaning on LED's for the dimming and as said if I take a hit I know the LED's won't be damaged.

You get 240lm at 1A with the SSC P4's which is ~a 20W halogen give or take. Having 2 x SSC P4's if you've never used highpower LED's or been exposed to high power LED light before is BRIGHT. Nothing wrong with the SSC P4 U-bins. It's cheaper as well. It's almost like getting two LED's for the price of one Cree Q5 right now. I paid $7.18 for the U-bins back then. Now they're more then $2 off. If I was you I'd go with the U-bins and save money.

I bought mine at Target for 24.95. Supposedly the Ray O Vac version of the same light is cheaper at Wally Mart.

Last question. How do you strap yours on your helmet?

I'd like to supplement my handlebar mounted light with a helmet light.

That's what I do (I use it in tandem with my 15 watt halogen flood and it covers everything I need to see), and fastening is the best part. If you have a visor on your helmet it's a snap....no strapping needed. You just tuck the strap of the headlamp under the visor on both sides and it stays very secure. It also has a top strap which stabilizes it further. The other benefit of that being you can take it on and off your helmet as needed much easier. If you don't have a visor you probably would have to strap it in....when I've done that in the past I used the smaller plastic zip ties through the vents in the top of the helmet. Just make sure where the "joint" is that you have that on top of the helmet or in the vent hole itself so that it doesn't press against your melon.

BTW, the other cool thing about it is the battery pack on the back also has a red led light that blinks or solid. Not real bright, but still noticeable and doesn't require an extra set of batteries.

I just figured out another advantage to having a headlamp on your helmet. You can use the strap at any point 360 degrees to put a flashing led light that clips on. You want side lighting? Just put one at 90 or 270 degrees on the strap of either side (based on the assumption that the front of the helmet is 0/360 degrees). I tried a 135 degree (or 225 depending on how you look at it) angle this morning which gave me some side view and some rear view. Approaching a busy intersection it might even be better to have it at 45/315.

Looks like that light on Nashbar may be a good find. If it's anywhere near as bright as a Dorcy one-watter (that uses PAR reflectors instead of TIR prisms), then this thing should be adequate for trail riding at a decent pace. They say that TIR prisms are brighter, but I've found that PAR reflector bowls are superior, but it may just be the light itself is a better light.

I got my 3W LED today at Target and I couldn't be happier. I started a thread on this in commuting thanking you ccd. I couldn't remember where I read about them so the thanks was anonymous. Anyway, it's a great little light that I strapped on securely in seconds. I wish I would have done this long ago. I haven't had a chance to do my commute with it yet but I'm psyched!

The Cat Eye headlight you list is essentially a 'to be seen' light only. Meaning if you're riding on well lite or partially lite streets, you'll be fine because you'll be relying on the street lights and car lights as your primary source of light. If you try to use this headlight on a pitch black side street you'll be able to see a small spot in front of you. It's enough if you're willing to go slow and/or you know the territory.

If you are traveling on well lite or partially lite streets and you feel being seen is more important than needing more light to see, I'd suggest a strobe. Cat Eye makes a 3-LED one I just bought at REI for $22.

I don't know about the tail light. I have the 10-LED Cateye light. With fresh batteries it is enough to hurt your eyes if you directly look at it. I'm sure there are brighter ones but I don't see the need. Keep the light high up near the seat. It puts it more in the line of site.

Apparently these 3W lights are available 2 for $28 at Costco or Sams. Good deal.