Altough you've already made your choice to go with a headlamp, you may consider getting a light for your PSK, a spare for your bag or something for EDC later on. You certainly don't
need a flashlight but they're nice to have sometimes and I personally wouldn't consider them entirely benign.
There arn't many single AA LED flash lights made nowadays but AAA and button/flat cell keychain lights are popular for small lights.
A Fenix E01, Fenix L0Ds, iTP A3 EOS(standard and upgrade), Maratac and Romisen RC-B3 are single AAA LED lights that will cost under $30 with the exception of the Fenix L0D which will cost around $40 depending on retailer.
The iTP A3 EOS "upgrade" and Maratac lights are essentially the same light, the two only have small differences but are roughly the same price(around $20 depending on the retailer) both come with a pocket/belt clip that can be removed and flipped so that the light can be clipped to the bill of a ballcap, to the band of a wrist watch or a car's visor, ect.. They are both Med>Low>High twist setting lights that run off a single AAA, the Medium setting(18 lumens) will last a few(3-5) hours and the low setting more than 30 hours on both lights. I've had the iTP upgrade for several months and the maratac for a few months.
The Fenix E01 will last about 10hours at 10 lumens then dim for several(5+) more hours.($12-18 depending on retailer) I've been using a purple Fenix E01 for a long time now as a replacement for my old maglite solitare(which is junk in comparison), the fenix is not as bright as my iTP AAA but it suits my needs and I happen like purple...
I don't own a Romisen or Fenix L0D, the Romisen retails between $15-20 depending on retailer and the Fenix L0D retails around $40.
The iTP A3s, Maratac and Fenix E01 will fit in a altoids tin or can be carried on a key chain without getting in the way, They arn't much larger than a AAA battery, the Romisen and Fenix L0D are slightly larger than the first three but may still fit in a altoids tin, I don't have either to check though.
www.Goinggear.com has the Fenix E01($12.50, several colors) and iTP A3s EOS lights($18.50-20.50, black or gray) among many other lights.
There are alot of cheap Button cell LED keychain lights(in various shapes, sizes and colors(including colored LEDs)) available at almost any walk in store like walmart and many gas stations for between $1-3. They can be bought in bulk online from places like
www.Dealextreme.com for about $5 for 10x lights(or $25 for 50x) or a single can be purchased from
www.Goinggear.com for $.99. The majority of these kinds of lights will also fit in an altoids tin, some are flat but may have unusual shapes which may get in the way of other items in your altoids tin. Most button cell keychain lights produce enough light to easily find your way around a dark room/building in a power outage or at your feet on a path/sidewalk at night and should last for several hours.
These button cell keychain lights are cheap, have decent run times, small and weigh practically nothing so you could easily carry one on your keychain along with your keys and not be bothered by it, it's there if you need it(if you don't have your shoulder bag at
that moment for example) so there's little reason not to carry one on yourself at all times.
