It's been a good five years since LED flashlights pretty much took over the "tactical" light market, but I've been carrying the same old xenon-bulb Surefire Z2 "Combatlight" for eons. It has an adjustable wrist lanyard on it and a narrow, flat-sided section in the middle that, along with the rubber collar behind it, makes it easy to use one handed, even wearing gloves, even if I have a pistol in the other hand.
Of course, the downside is that the xenon bulb sucked the electrons out of those expensive lithium batteries like a shop vac in a Dixie cup.
Last gun show, I finally got around to upgrading to the LED version, the Z2S, which is not only brighter and has a longer run time, but also has a strobe function, whose utility I am not entirely sold on.
I thought about just upgrading the lamp assembly, but while it would have been about a third cheaper, this way I can take the older flashlight and keep it in the car for emergencies and suchlike.
(Staying with the same model of flashlight also allowed me to move my GG&G T.I.D. over to the new one. I can't think of any possible situation where I will ever hit somebody with a pocket flashlight, but it looks cool and I got it on sale, so what the heck.)