This instructable is an entry in the Pocket-Sized Contest, so please vote!
This instructable is an entry in the Hurricane Laser Contest, so please vote!
This instructable is an entry in the Green Tech Contest, so please vote!

Ever need a flashlight, but don't want to lug around a big one? Or you wanted to use something that didn't take up as much energy as a regular-bulb flashlight? Then this flashlight is perfect for you! This is really easy to make and only require a little bit of knowledge in electronics. This is also better than most altoids lights because you can change the battery if needed and it uses 3 LEDs rather than one or two.

WARNING: THIS INSTRUCTABLE USES POWER TOOLS AND ELECTRICAL COMPONENTS, I AM NOT RESPONSIBLE FOR ANYTHING STUPID YOU DO TO YOURSELF WHILE MAKING THIS FLASHLIGHT. WHEN USING THE DREMEL, IT DOES MAKE SPARKS, SO BE CAREFUL AND WEAR SAFETY GOGGLES!

Step 1: Ingredients

1- Altoids Tin (or Small project box)
3- 5mm High-Brightness LEDs
3- Snap-in LED holders
1- Switch of your choice. I used a sliding STSP switch.
1- 9V battery, or other battery. Just know how much power your LEDs need and what resistance to give them. I used this instructable to find out how much resistance to use.
1- 9V battery snap
Some wire
Wire cutters/strippers
Solder & Soldering Iron
Heat Shrink (optional)
Electrical Tape
Drill will assorted drill-bits
Dremel with cutting wheel & sanding attachment
Safety goggles for when using power tools

Step 2: Wire the LEDs in Series

The short lead of the LED is negative, and the longer lead is positive. Bend the positive lead of one LED and the negative lead of another. Slide some heat shrink tube on the lead of one. Make hooks on the end of each lead and connect them, then solder. Now slide the heat shrink tube down and shrink it up with a lighter. Now, get the LED you bent the positive lead of and bend the negative lead. Bend the positive lead of the last LED. Connect the two bent leads the same way you did before. I forgot to use heat shrink, so I just used electrical tape to seal it.

Step 3: Adding a Switch

Solder a short piece of wire to the positive lead of your LED set-up. Use heat-shrink to seal the deal. Now solder that wire to one of the leads on your switch. You might want to use heat shrink or electrical tape around the connection between the wire and the switch to ensure it doesn't touch the other lead of the switch.

Step 4: We Need Power!

Before soldering, make sure it works!!!

Solder the positive lead of the battery snap to the other lead on the switch.
Solder the negative lead of the battery snap to the negative lead of the LED setup.

Use heat shrink when needed.

Note: I didn't need resistors (unlike most LED projects) because I was using a 9V battery and each LED required 3V to light up. (3 LEDs x 3V of power per LED = 9V of power total)

Step 5: Mounting LEDs

Get out your LED holders. Position the LEDs on whatever side of the Altoids tin you want, and make dots with a Sharpie on where you need to put each holder. Starting small, drill holes until you get the right size for the holder. Repeat for the other dots you made. Put the holders in the holes you drilled. Now place the LEDs in their holders. You should probably put electrical tape around at least one lead of each LED to prevent them from making contact.

My LEDs weren't really "snapping in" to their holders, and I drilled my holes a little too big, so I just used a little super-glue around the holders and the back of the LEDs (try not to get glue on the front of the LEDs because it dries white and will reduce the visibility of the light).

Step 6: Insulate Tin

Put electrical tape anywhere in the tin that leads might be exposed.

Step 7: Mounting Switch

Decide where you want the switch. I wanted mine on the short side of the tin. Since I'm using a rectangular switch, I need a dremel to cut a notch in the side of the tin. Use a marker to mark where you need to cut. You need to cut between the edge of the actual slider and the screws. This way, you can slide the switch freely and still have a place to screw it in on the tin. Be sure to wear safety goggles because cutting the tin with a dremel does produce sparks. After you cut the notch, put the switch in a drill tiny holes where the screws will go. Screw the screws in until everything is nice and tight.

Step 8: Done!

Now just snap the battery in, close the tin, and you have a nice LED flashlight! Hooray!

Step 9: Hurricane Laser Cutter...

Now, since this is in the Hurrican Laser Cutter Contest, I need to tell you what I would do with one of their amazingly cool and awesome and robotic laser cutters.

First of all, I like to do papercraft. Now I am using a hobby knife to cut all the pieces out, which makes it look terrible and is very time-consuming.

I also like to do some woodworking, and this would allow me to make precise cuts on my projects.

Third, my dad runs a service called Memory Links (www.memorylinks.com) and has to send his pieces off somewhere to get them laser cut. My dad would most likely be very excited if I took the laser cutter to his office so he could manufacture his own Memory Links.

Fourth, I make paracord bracelets and have been wanted to put dog tags on them. I have the dog tags, just no way to put custom messages on them.

Wow, I have a lot of uses for a laser cutter! Please vote for me!

Wait! One last thing. I will also post an instructable on everything I do with the laser cutter if I win it!

Thanks!