Streamlight Enduro.

This used to be marketed as the River Rock Headlamp sold at Target.

It is regulated, waterproof, lightweight and pretty tough. Feeds from 2xAAA's. I have a bunch of the River Rock versions and have given some away as gifts.

The original 0.5W LED had a bluish tint. I don't know if they've upgraded. If you Google "streamlight enduro modifications" etc. you will find instructions for installing a better LED.