Total project time was well under an hour, including thinking "Hey, I want to make a flashlight" and "I wonder if I have everything on hand to make one."
Even without the wrist strap, it's great for slipping in your pocket - just in case it's needed.
Apparently I have to write something in bold stating that this is in the Pocket Sized contest in order to get any votes. I've noticed that all the Instructables that do this get a heck of a lot more votes than this one, even though I was the second or third to enter the contest. Please vote! Maybe if I keep writing I'll get more votes than other flashlight projects basically identical to this one that were posted after mine.
Step 1: The Parts
This was made with:
1) four 17,000 mcd clear white LEDs
2) one 10 ohm resistor
3) one tiny SPST switch
4) some perf board
5) two AA battery holder
6) two AA batteries
7) mounting tape, although hot glue works better
Naturally not everyone is going to have super bright LEDs just laying around their room. You can use any bright LED you want, but the brightness will be different.
Step 2: How It's Put Together
1) Orient each LED in the same direction and solder them in place. Connect all of the positive leads together and all of the negative leads together.
2) Solder the resistor and switch in place.
3) Solder the red lead from the battery connector to one side of the switch, and connect the other side of the switch to the resistor.
4) Connect the other end of the resistor to the positive lead chain of the LEDs.
5) Connect the black lead of the battery connector to the negative lead chain of the LEDs.
6) Mount the perf board to the battery holder. I used some mounting tape, although hot glue would hold it much better.
Step 3: But Wait, There's More!
This was made with some webbing and Velcro. After a quick tutorial about how to use a sewing machine, I tried my hand at it. Came out pretty well. The little pocket was made by folding some webbing together lengthwise and sewing the sides together.