You are likely to be eaten by a Grue!

[Tigerman]

I carry a UK Mini Q4 (4*AA) LED ligh in my BC pocket on pretty much all my dives. For night/wreck/other dark stuff dives I carry a UK C8 (4*C-cell) LED light as my primary.
Tank lights like glow sticks or strobes can be handy, especially if theres different colors on different people as it makes it a bit easier to distinguish eachother under water in the dark. If youre just two people diving (or PADI forbid, youre solo) it might not be of THAT much use unless you lose or have both/all the lights crap out on you and your buddy need to find someone swimming around in the dark with no light source..

 

[soamelt]

My main light is a UK HID Sunspot. I love it, but it takes 8 C batteries to run for 3 hours. It gets expensive to run. I've used the 4 C battery UK LED which is pretty nice light also, much cheaper to run and the bulbs are much cheaper and less fragile than my HID. I also dive in south Florida where the vis is usuaully pretty good, the LED is nice, but I LOVE the HID! Anyone who has web down with me at night either wants my light or has since purchased an HID.

For backup I always carry day/night a UK Q40 LED which works well for under ledges and should my primary fail.

I use a glowstick instead of a tank marker.

 

[damage]

I carry a main light (princeton tec torrent led) and a backup (UK PCa led wich I carry in all my dives) Definitely go for the led; pricey at first but you'll save a lot of $ in a log term with the batteries.

I recently bought flashing sticks but I have not used yet.

 

[overkillphil]

Saspotato, that's too funny! I too have the PT Shockwave, and I too have already had bits falling off of it in only 5 dives. The combo set is a decent starter kit, but my next torch purchase will be either the Salvo Rebel 21 watt LED or the Dive Rite LED LUX canister light.

 

[mikemill]

All in all I generally carry 4 lights with me on every dive (as sometimes the daytime can get real dark). Two UK LED lights, a good size light mounted to the top of my camera (focus light and my primary light when doing photography) and if the $&%@ really hits the fan my strobe has an aiming light.

 

[trintrax]

I use a Hartenberger maxi LCD 50W as primary lamp. I am mainly diving in mountain lakes with viz under 3ft. The 50W bulb can be boosted to 125% what gives nearly the power of a 100W lamp when using a HLX Halogen bulb.
My second lamp is the amazing Scubapro Nova Lamp.

 

[Santa]

flashing tank markers spoil the atmos ... dont become another underwater pin ball machine