I tried an LED headlamp the past three nights. I'm surprised how little it affected my night vision. I was still able to see pretty well outside the light pattern.

It has 5 LED bulbs and a high and low setting. I used the low setting. The box claims 17 hours of use on 3 AAA batteries. I haven't tested the limits yet.

The headlamp cost $12 at the Battery Store. It's made by Rayovac.

In the future, I'd like to get a solar headlamp.