While I have a bunch of flashlights I have yet to find anything as useful as my Princeton Tec EOS Rebel LED headlamp. I probably have 6-8 of these stashed all over.

It packs small (1.75"x2.5" - think palm-sized), is amazingly bright, has a great quality of light (smooth), covers a nice field of view (for my uses), is regulated (keeps max light as long as possible), has 3 really nicely selected brightness levels (blast, most uses, and inside tent), lasts a long time at low (50 hrs regulated + 71 hrs declining) & medium (10 hrs regulated + 105 hrs declining) settings, even high setting has 1 hr regulated + 112 hrs declining, easy to change the three AAA batteries with no tools, lithium batteries OK, waterproof to 1 meter, ...

... and being a headlamp it can magically point to wherever I am looking ... OR you can just hold it in your hand with the strap wrapped around your hand for security ... OR you can wear it around your neck for even more security.

Also, based upon my experience, that elastic strap lasts a long long time - that was one of my earliest concerns, but after quite a few years they show NO sign of aging or wear.

All for less than $35 on-line. That's why I have so many.

I can't think of too much of my gear that I think is as first rate as the PT EOS-R headlamp ... OK, my RSK Mk1 and my Garmin GPSMAP 60CSx, beyond those my favorites aren't so focused on a single brand/model.