Your source for everything evil!
If you want a beautiful piece of artwork to decorate your body, this is not the article you're looking for. If you're looking to start a gang or revolutionary group and want all the members to have matching symbols on their arms, this is the article for you. This method can be done easily and anywhere with very accessable but will be quite painful and, depending on how nible your fingers are, dangerous.

What you'll need:
1 cheap disposable ballpoint pen
1 the thinest needle you have
Any kind of tape
1 lighter (or matches/fire source) (optional)
Bandaging material - ace bandage, gauze, thin rags, etc

Instructions:
0.) Optional: before you disassemble the pen, feel free to draw out the design you are going to tattoo.
1.) Disassemble the ballpoint pen. You should now have a hollow outer tube and a thinner inner tube containing ink with the tip of the pen on it.
2.) With the thinner inner tube containg ink, take off the tip of the pen such that you can touch the ink in the pen. Throw out ballpoint tip. Set aside ink filled tube.
3.) Take the needle and tape it halfway onto the larger hollow tube such that the pointy end of the needle is pointing out. If you can shank someone with this little contraption, you are on the right track.
4.) Optional step: Using the lighter or alternative fire source, sanitize the needle by putting the exposed part of the needle in the flame. Note: though this step is not manditory for overall success, it is highly recommended in preventing diseases such as tetanus.
5.) Now you are ready to make your tattoo! Using the pen shaft as your handle, stick the end of the needle into the ink so that the tip of the needle is coated. Now this is the part that you have to be careful. Stick the needle into your skin. The tip of the needle should land in the Dermis, the layer of skin just under the epidermis, the outside layer of skin. Note: hairs grow out from the hypodermis, the layer under the dermis; so if your needle is as deep as the root of a skin hair, you've gone too far. The spacing of needle pricks should be as close together as possible. Another note: don't be alarmed at the amount of blood that may come from getting a tattoo. It will heal up.
6.) After you have successfully made your tattoo, very lightly wash off any blood/excess ink and bandage it up tightly. Leave the bandage on for a while. Everyone has different views on how long to keep it bandaged, so leave it on for a MINIMUM of 2 hours and up to a day longer after that.
7.) Your done! As I said before, these are pretty much to get a message across, don't think these are going to look like tattoos that you get with real tattoo tools at a tattoo parlour. Now you can go tat your friends and family! Have fun!