This is what I'm currently using, primarily for caving. The front helmet mounted light and associated battery is a Taglite I. The light head is a Nite Lite model with a halogen bulb. With the application of a little silicon it can be made to be waterproof. The battery is a rechargeable gel and with a full charge will go 8-10 hours.
As a backup I have a mini-mag shock-corded to the helmet side. The standard bulb has been swapped over to a LED. Not the brightest light but good to have. About three years ago I had to negotiate about 2 miles of cave passage just with this light after the main light failed.
As a backup I'm carrying a Princeton Tec Apex and have also been using this light for general purposes. Good in the caves, good in the woods, and good under the hood.
As a backup I have a mini-mag shock-corded to the helmet side. The standard bulb has been swapped over to a LED. Not the brightest light but good to have. About three years ago I had to negotiate about 2 miles of cave passage just with this light after the main light failed.
As a backup I'm carrying a Princeton Tec Apex and have also been using this light for general purposes. Good in the caves, good in the woods, and good under the hood.