In my opinion, the best, most all-around versatile light is the headlamp. They might look a little goofy, but they're functional and hands free lighting. Setting up a tent, working on a car, lighting a fire, and more other camp chores require use of BOTH hands. Holding a flashlight in your mouth gets old, fast. Most headlamps these days use LED lights and run for dozens of hours on a set of batteries.
In my personal kit, I rock a Petzl Tactikka Adapt XP.
It's a great light. The red filter can be slid on and off--red light is more easy on the night vision, less visible from and distance, and also good for spooking out friends and family. The "Adapt" part means that it can be detached from the headband and used on a belt clip or a special adhesive mount, which can be attached to helmets, etc. The versatility is worth the extra couple dollars over the Tactikka XP model. It's night amazingly bright, but provides more than enough light for work and hiking. A boost mode can provide, well, a momentary boost of light when needed. The headband is also surprisingly useful for hanging the lamp from a branch or tent ceiling to light an area. I've found the headlamp to be comfortable to wear for extended periods, something that concerned me before I'd tried one out.The Tactikka's will run for a manufacturer's claimed 120hrs on low mode. Real-life use will vary, but they will run a LONG time on one set of batteries. One complaint that I do have is that they run off AAA batteries. I'm a big proponent of standardization in preps, and MOST other lights and electronic devices out there seem to run on AAs or CR123A's. Keep that in mind while you're shopping around, especially if you're already planning on carrying AAs as backups for GPS, radios, and so on. For me, it's not a deal breaker. AAAs are at least tiny and easy to pack.
I'm going to interject here with a slight complaint: glow sticks. Sure, they are good in SOME situations. No spark, no chance of blowing anything up by lighting them. Work underwater. Provide light for several hours. Disposable, can use for marking trails and so on. BUT, for their space, most people would be better off stocking up on BATTERIES. For starters, your glow sticks will hit their expiration LONG before your batteries do. A fresh set of batteries for a headlamp will give you, say, 50 hours of useful, on-demand light. A glow stick provides a few hours of constant, but fairly dim light, and then is useless. They've also got that annoying, crinkly wrapper. It just seems like a no-brainer to me: batteries win. If you're worried about needing a backup light, HAVE ONE!
Petzl and Black Diamond are two of the better brands of headlamps. I have no experience with Black Diamond, but can whole-heartedly recommend the Petzl Tactikka. I've got some posted in the TEOTWAWKI Blog store, and they're available at most major sporting goods stores and places like TAD GEAR.
If you're one of those holding out against a headlamp b/c they seem stupid or goofy looking, then you've got to try one out. Really. Go camping. Wait until dark to begin setting up your tent. Try it with a normal flashlight. Give up in frustration and humble yourself to the pure utility of a headlamp. There's no better tool for all-around lighting tasks.
