Astronomical Headlights?

[angotja]

What's up with helmet/handlebar-mounted headlights that cost $300, $400, and up (ex brands: Nite Rider, Light and Motion)? Is it absolutely necessary to spend this much to have effective/reliable illumination for safe traveling at night? What are some reasonable alternatives? What do you use on your bike, and how effective is your means of illumination?

 

[rek]

The ultra expensive lights are HID-based (think the bluish looking headlights on new luxury cars) units that are designed more for long distance off-road riding; things like 24 hour mountain biking events etc.

On my road bike, I use a simple white LED flasher for the front and a red flasher for the rear. On lit city streets the #1 priority is making sure others see you; the city street lights are good enough for seeing where you're going.

I haven't had any problems with people not noticing me on the road, but then again I'm always ultra paranoid and aware of what's going on. (It kind of disrupts the pure enjoyment of the ride, but it keeps me alive)