In this instructable we are going to create an (organic) oil lamp. They are one of the simplest way to get some light, and were used for several millennia.
The lamps shown here are more on the chic/neat part of the scale, but as you will find bellow, oil lamps can be made from about everything. They can be handy in case of blackout, or simply decorate/give a calming ambiance to a room.

Difficulty: very easy,
Tool requirement: basic (almost none),
Time: about 15 minutes.
Cost: none to a few euros, depending the container you choose

One last thing; this instructable is an entry of the 'Oil challenge', so if you like it, do not forget to vote!

Step 1: Requirements

Tools :

A drill (a manual one is enough), or a strong knife in last resort (strongly not recommended)

Materials :

A container (bottle, can of soda, jar...),
Some cotton thread or rope for the wick (or a purchased wick)
Some vegetable oil.

Step 2: Step 1 Choose and Prepare the Container

The first thing is to find a container that fits your need (room decoration? emergency light?). I bought two nice bottles in a decoration store, but any container can be used. Actually, there are only two important things :

if the container has a lid, this lid must be drillable,
the container and lid must be impervious and not burn or melt on a open flame... but you may have guessed that.

There is even no need to use a covered container: the first oil lamps were open. I would not recommend using them though, as they are the best way to stain everything around with oil, because you are going to spill it sooner or later...

Here is the moment to use the only tool needed : the drill. Remove the lid of the container and make a hole of about 5mm. Do not drill it while on the container (you may break it) and hold it firmly on a sacrificial board.

Step 3: Step 2 Prepare the Wick

The wick material must sustain the flame temperature, so most of the synthetic strings are unusable. It is important that the wick is not too tight : they have to be saturated with oil, and the more tightened, the less oil. Their diameter should allow them to be stuck in the lid hole, but again not too tightly.

The best choice is usually cotton thread, because it is cheap and can be found easily. You can buy a dedicated wick, but I found more interesting to make my own. You can also use a cotton rope, but it is likely it will be weaved too tight. Note that a shred of a cotton cloth may be used as well!

A single thread being too thin, you will have to braid or twist it as a thicker wick :

The first solution is to braid the thread; it will give a nice looking wick, allows adjustment of its tightness, but may be a too cumbersome process even for a short wick. If you choose this solution, here are some resources to learn how to braid 3 strands, or 4 strands, etc.
The second solution is to simply twist the thread, like shown here. You can twist it using your drill if you want, but do not twist it too much as it is easy to overtighten it this way..

Step 4: Step 3 Use It!

You can now fill the container with oil, pass the wick through the lid hole, and screw or attach the lid to the container. The wick should not protrude more than one cm; more will actually produce a poorer flame and some smoke. Check the wick is soaked with oil, then light it. Voilà!

Even if it might be tempting to add perfumes to the oil, keep in mind these substances will burn, so the smell may not be the one intended. Another consequence may be the release of some unhealthy fumes. The best way to perfume your house is to use an essential oil diffuser which vaporizes natural oils without heating them, or a fragrance lamp which disperses scented alcohols by heating (but not burning) them.

Some word of safety :

Use only organic oil in these lamps (they are hard to lighten), not fuels that are a lot more flammable!
Don't overfill the oil container; there should be a gap between the oil level and the open flame, for more security.
Keep oil lamps out of pets and children's reach so they don't play/get burned with them, knock them over, or drink the oil.
Finally, do not leave oil lamps (or actually any open flame) in unattended areas.