#DYI diffuser. Ever since I was a kid, I always carried a Swiss Army knife. (Feel nekkid getting on a plane without one.) And with the advent of LED lights, been carrying one of those for the past 20-25 years. They have gotten so much better. Anyway, for as long as I remember, I have carried a small AAA flashlight. Now they are brighter than the old security guard Maglites. A cap from an old Chapstick makes a great diffuser to change the beam from one that throws any distance to more of an area light, like a lightbulb. I have tried it on a couple of different lights and they fit. Obviously, your fit will depend on your light, but it works great. It stays on snugly and if I need to see a little farther, just pop it off.
Then there was the paranoid dyslexic who tells his psychologist, "Doc, Doc, I think I'm following someone!" You aren't paranoid are you?
For some reason I read the thread title and thought this was going to be about diffusing essential oils.