We have covered plenty of interesting flamethrowers in the past. Want to build your own? NightHawkInLight has posted a video that shows you how to just that. You are going to need a soda bottle to get started. This flamethrower lets you use a solid fuel, so it is less dangerous than traditional flamethrowers.
To get started, fill the bottle with starch and seal it to create a closed system where squeezing the bottle forces a jet of the fine powder out of the front to be ignited by an open flame. As you can tell, the design is pretty simple. Watch the above video to get a better idea how to make your own flamethrower.