I bought this originally as a backup light to stash on my bike somewhere, but it is just too nice not to use regularly. It is tiny - about the size of a walnut - and is mounted on a clever base, which allows it to swivel in any direction and also has a clip if you don't want to use the headband.
It has settings for high, low, red, and strobe, as well as a lock setting so it doesn't turn on accidentally in your luggage. It also has a weather resistant storage case and a 10 year lithium battery.
This is my first head light, and it is a real step up from clenching an AA Maglite in my teeth while drooling on myself.