Maybe the Folomov 26650s
The Amutorch X9 is pretty compact.
I’d give a +1 to this! I have the DN35 and despite the button, it’s a nice compact little light for a 26650.
The Klarus G20 would be my vote if you wanted something more floody, the DN35 is definitely more throwy.
The A8 is a fave of mine, but it really needs an emitter upgrade. 
Thrunite TCS20 , MHvast TS70
Been thinking this one over, love the light, amazing tight hotspot. It rivals the UF2200 for beam tightness. I am thinking that it needs an XHP50.2 in 4000k.
Wasn’t there a Haikelite (SC26?) nicknamed “Li’l Fatso” when it took a shorty tube for a 26350, but normally comes with the “regular” tube for a 26650?
That was about as small as I’ve ever seen a 26_50 light.
I got the wife one in blue a few years back, she loves the SC26.
I think the biggest issue is 26650 is simply not a popular format. Even the smallest 26650 light is too big for comfortable pocket EDC. And for larger lights, you get better capacity with multiple 18650.
Also, because 26650 isn’t popular, the cells tended to have not kept up with the latest technology. The best 26650 is not as efficient per unit of volume as the best 18650 or 21700.
I’ve noticed the same problem with 18500. It sucks that the best high-drain 18500 has the same 1100mAh capacity as the best 18350.
I agree on the fact that 26650 cells are not as advanced.
If 26650 cells were as advanced as 18650’s, or 21700, I would guess we should be seeing a capacity closer to the 7000 mah.
I personally prefer single cell lights, so would rather a single 26650 cell instead of 2 or 3 18650’s, but it seems like the market is in favour of multi 18650 lights so there are def more options there.
Haikelite SC26?
Elisa’s dv2s, mfo1s, convoy m3, nightwatch ni40 ( with 90.2) and tons of others….
Convoy S11 139 mm long x 33mm diameter 171 gram.
Well this is an old thread but right now, for a compact 26650 it’d have to be this beasty: https://www.aliexpress.com/item/4000170457613.html
Mateminco MT07 or Astrolux MF01 Mini
This beasty starts out glorious, but drops the output pretty much instantly no matter the temperature setting or battery used. I don’t think it even brings the lumen up when the head cools down , you can reapply turbo but that’s all you can do. Between that and a smaller , weaker d4sv2, I pick the emisar by the pattern of reducing lumen output.
There is tons of compact 1 26650 battery lights, For me personally the search is to single out those with a slim profile and sustainable output of no less that 2,000 lm or so. This has been a challenge. There is a couple that come close like mhvast ts70 or thrunite ts20 with around 1700 sustainable, and reportedly some other not really not a whole lot unfortunately. Most of these settle at around 1,000 lumens which is not enough for me….
I would not get any 26650 and expect it to be compact.
That is relative of course.
The other thing is, 18650 cells are more advanced, and usually have way higher energy/volume numbers, as well as higher peak drains.
At least for the price - you may be able to get better 26650s but I don’t consider anything over $5 a cell reasonable.
But that is all just me.
Yes size is relative. Also perception wise it’s relative to the output it provides. If. 26650 light produces 1000 lumens I may not call it compact but if it produces 7,000 then I probably will call the same size light compact. In general, to me 26650 is still compact as it fits in the pocket easily and I can wrap my hand easily around it and it’s quite short too.
I agree 26650 are not as efficient as 18650, so what? They still have larger capacities and for most applications are available with sufficiently high drain variety. I for one don’t mind paying a few extra $$ to attain a light that I will enjoy more…
7000 lumens would be over 25A, not sure any 26650 can do that
just saying
i have a wuben t50 i think, it;s good - but i almost never use it
it;s a floody 2000 lumens +
wle
I probably said this before but the Amutorch X9 is compact, has USB charging, stepped or ramped modes and can sustain high(not turbo) pretty well.