Can't anyone go to their local radio shack, purchase a little baggy of L.E.D.'s from the electronic components bin, batteries, and some tape / wire and make like 40 flashlights? You can use switches if you want to get fancy...
I don't go that far for switches or handles,
All I use is a couple of the 'button' batteries (Cells) stack them for 3 volts, the threshold voltage for a lot of the LEDs, and use a cloths pin to hold the batteries and LED together and make a handle for the 'Flashlight'.
That is if you are too cheap to pay the 59¢ for the entire thing at the local 'Dollar' store for the key ring version.
The batteries about the size of a nickel to the sized of a quarter work the best.
A single 3 volt 'Button' cell will work if you can find one.
Look for, or ask for, the batteries coming off the racks because they are outdated, you can get them CHEAP!
If you try this, REMEMBER!
1. Diodes are polarity sensitive.
They won't work if hooked to the batteries backwards.
Turn them around and try again if it doesn't work the first time.
2. If you use something like a 9 volt battery, you MUST use a resistor to keep it from burning out the lower voltage diode.
That's why the little button cells are so good for this, they don't put out enough voltage or amperage to smoke the average small diode.
3. Anything that is non conductive will work to keep the parts held together.
If you solder, just solder one leg of the diode to each side of the battery, and let natural forces spread the batteries apart to shut things off,
Pinch them together to make the 'Flashlight' come on.
4. If any of you have 'Light Amplification Night Vision' equipment, or infrared night vision equipment, check out a IR or Infra Red diode.
(or just point your TV remote at the night vision for a sample!)
You can see it plain as day through your night vision, but it's invisible to the human eye!
Cool toy!
Instant picket line too!
Set a few singles, or string out wired set of IR diodes and fire them up at night...
Anyone moving through the field will appear to be walking in daylight, when in reality they can't see them and think it's too dark to see them!
Just for the IR junkies, there are IR 'Light Sticks', the chemical lights you snap and shake!
Those will shine for hours with no battery power at all and the light they emit is invisible to the human eye, so know one knows you have illuminated the area.