One of the coolest pieces of kit I took over to Afghanistan back in May was my brand new Gladius Maximus flashlight from Blackhawk.
I had previously deployed with a Surefire light that loosely approximated the LX2 Lumamax and liked it a lot for its heft and bright, direct light.
But the Gladius takes the concept of an "illumination tool" to a whole new level with its ability to change from a constant illum, thumb-press illum or flashing light with an easy rotation of the tailcap.
The GLADIUS MAXIMIS is quite possibly the most innovative handheld tactical illumination tool to arrive on the scene. This is a 6 volt, lithium battery powered, high-output LED, highly water resistant, aluminum bodied, illumination tool designed primarily for handheld use, but robust enough for weapon mounted applications. The Gladius Maximus is designed from the ground up to be immersed into the realities of close quarter conflict and should significantly enhance the capabilities of those operating in low light environments.
One of the things I liked best about the Gladius was its dimmer function: hold the button down while the steady beam is on and the light gets progressively dimmer -- a nice feature when you're using the Gladius to find your snivel gear in the hooch and don't want to wake everyone up with the high beams.
Of course, I'm a journalist, so I use my light as a tool to see what I'm reporting on and also as a last ditch defensive measure to blind an attacker so I can run. But Blackhawk says their Gladius Maximus is well-suited to weapons-mounted applications -- though I will say it seems a bit large for attaching to the end of an M4.
About a year ago I went to Blackhawk for its writer's seminar and one of the classes we went through was a quick syllabus on how to use illumination tools in tactical situations. The class demonstrated that variety in how you light things and when is key to disrupting a potential attack. With the Gladius you've got all those different options right there built into the functionality of the light -- one less thing to think about when the bullets are flying.