While not entirely pocketable (pocket light) look at the medium sized/medium distance throwers that run off of either 3, 4 or even 8 AA, such as the Sanyo Eneloops that SH mentions.
NiteCore EA4 ($55ish shipped)
JetBeam SRA40 ($95ish shipped)
EagleTac GX25A3 ($95ish shipped)
Sunwayman D40A ($80ish shipped)
Fenix TK-41 ($130ish shipped)
These lights run on ubiquitous AA batteries and work really well on the rechargeable NiMH types, that you'll want anyway vs. the alkaleaks.
There are other smaller, more slender lights to consider, like the Fenix PD32/PD35, NiteCore P12, EagleTac D25C2 and something like the ZebraLight SC-600 mkII, but these either use lithium-ion cells, or 2xCR123A photo batteries and these two power sources can be a bit more involving, or expensive, or even both.
They listed lights above offer bigger ~40mm diameter heads, so the reflectors can be deeper/wider, for better throw, they can pump up the lumens to that mid 850-1000LM level, most have variable modes, strobes, SOS and beacons, so they're flexible and while a bit fatter in the palm, I carried my D40A in my pocket last Friday and it wasn't exactly a gold bar, so doable.
The next form factor in that mid-level range, takes shape with a broader, wider head and longer more slender handles, which need to be carried on a belt, or in hand. Throw might be a bit longer, but not a whole lot.
Google Klarus XT-30 or JetBeam BC40, if you want, to see what I'm talking about.
Chris