Elzetta, Maglites, PKDL lights, or Streamlights depending on the task at hand. Oh, and I'm certain I have a SureFire or two to pick from.
Using primary fuel.
If it involves 'what do you rely on every day?' I'd say PKDL because that is my EDC lights.
Well considering that I find myself in dark places that are foreign to me I am relying on mine to keep me alive every day,this is what I considered in answering this.
I already carry and use mine all the time.
Yesterday I was in the basement of an over 100 year old high rise building that was a Hotel at first and now is luxury apartments and has been through several extensive renovations over the years.
I had to find a control panel in a sub basement where I had never been before and was not at all sure where I was going.
Of course the lights down there are on Timers and I could easily still be wandering around down there if I had to rely on my phone for light like most idiot techs that I come across down there?
It was certainly more disorienting when they started going off but also just an adventure as I knew I would not be in the dark if things went the way I have planned.
This kind of thing happens all the time and I am often the only guy in the dark holding the light.