I'm liking the armbands as a way to identify your friends and I keep thinking something similar with the chem lights would be awesome. I realize this makes you vulnerable to bandits, but I would love the option to attach a chem light to your backpack zipper so it just hangs there on the side/bottom/whatever. That way you could run as a pack of friends in the night and see each other easily. Again, yes, you would be super exposed. But that happens regardless. Just being able to distinguish who's on your side AND be able to see in the dark a tad more would be fun.
