I just added a Dereelight Javelin to my collection. I did a lot of research and discovered that many claim it's the longest throwing AA flashlight on the market. After testing in drains, a few buildings, and an abandoned limestone mine, I have to say that it's probably true.
It has three modes: high, medium (25% output), and low (.8% output, I think). Each mode is activated by depressing the button halfway, and the Javelin's memory remembers which mode you last used regardless of how long it's been shut off.
I also purchased an extender that allows it to use a third AA battery, and I find the added length makes it easier to use (not too long, easier to hold).
If you want a good AA flashlight, then definitely check out the Javelin.