This topic may be of some interest to the ladies, but will primarily be of interest to men because it doesn't completely eliminate hair. It turns out that fire, be it from a cigarette lighter or flaming ball of cotton, is actually a very quick, cheap, and effective unwanted hair management tool. I first started using it to remove a stray hair or two sticking out from my ears, and those stay gone for a week or more. More recently, I have started using it reduce the chest and armpit hair down to a manageable level without leaving stubble.
Several important points to remember:
(1) Hair does have a BTU value. That means, don't try to burn large volumes at one time, or you will get burned yourself. Best approach is a "controlled burn" approach of doing it every week, etc. (2) NEVER apply any accelerants to the skin. There are a lot of idiots on youtube doing stunts like this. Don't be one of them. (3) When first treating an area, start at the top (because heat rises and flaming hair will set the hairs above it on fire), then work your way down. (4) Try to do it right before taking a shower because it will leave behind a lot of ash and partially burned hair that needs to be disposed.
For the ears, there actually is a technique practiced by Turkish barbers to soak a cotton ball in rubbing alcohol while holding it with a set of tweezers, then set it on fire, and very quickly place and remove it from the ears of their customers in order to cheaply and quickly remove the ugly ear hairs. The key is to create a flame that lasts long enough to burn up the hair without burning the skin. With thin, long, stray hairs in places they don't belong, that is actually very easy to do. With thick and dense hairs close to the body, not so much.
I personally just use a cigarette lighter and nothing else, either by briefly moving the flame near the hair or quickly flicking it. I shave below the waist, but use fire to manage unwanted hair above the waist and this eliminates the problem of having a sharp boundary between the two. The benefits are that it's cheap, quick, painless, and leaves no stubble. However, it probably won't be of much use in the bikini area because the hairs you are controlling there are too large, dense, close to the body, and can't be seen.