I was thinking a LED insert with the right sized lithium ion battery pack and a diffuser would make for a cool little 100-200 lumen pocket lantern. Something to use the way they use lighters in movies only you know more output.
Has anyone ever done it? I’ve seen the cheap ones on Amazon but that’s not really what I’m looking for.
I thought about it for an old lumens build years ago and talked with CRX about in in some PM's.
my suggestion is to Not talk to CRX about anything because you will feel small , insignificant and unworthy when he sends you 14 pics of lights he made with a similar concept .
Instead i took out my coloring book , crayons and vowed to not color outside the lines
In all seriousness, CRX is great but his skills are mind blowing:
Just to be clear, CRX is friendly and won’t talk to you as if you are small, it’s his skills that can be humbling as myself and Boaz have found out 
This is his war lighter thread: CRX Brass War Armor Triple Light-er
wow, just wow. it looks more like jewelry than a light
My favorite is the Tesseract, CRX TESSERACT
That’s pretty cool. I was thinking more with a diffuser.